When you have a lemon make a lemonade :-)
12-10-2017, 09:08 AM
#12
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12-10-2017, 09:14 AM
#13
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It look clear to me as well, so I don't think that the coolant is ending up in the oil pan the laws of physics the level of oil is the same on the dip stick every time I checked and not missing so it's not burning oil
12-10-2017, 09:17 AM
#14
AudiWorld Super User
Catching up, various reactions:
1. The engine codes being there in earlier scans but then clearing with no work explained that should be affecting them is not making sense to me. Maybe a harness wire was disconnected at one point, or codes were not cleared from some old issues? In any case, as long as engine is running correctly, we can move past that. But, if not, work needs to stay focused there too to resolve.
2. The coolant leaking:
a. As another member mentioned, if the reservoir is leaking, it needs to be replaced. Does it have dripping or leaking?
b. Do a complete inspection again for coolant leaks, if you are saying it is still losing coolant. To be clear, are you saying coolant level still drops or not? Some incremental ideas:
i. In looking for leaks, look for any pink discoloration, slight pinking stains or fluffy pink powdery material. The pink comes from the coolant as it evaporates or burns off. If it is burning off, that would explain why you don't find it on the ground.
ii. Take the belly pan off under the motor and look there, both for leaks and for the stains. The top side of the cover is actually a simple great diagnostic tool if you just study what has landed on it over tens of thousands of miles. If you find anything, trace it back to source. In doing so, also look at front lower edge of radiator, and the part of the belly pan cover that comes near that area. If radiator has only a slight leak, ir will likely burn off/evaporate from the engine heat, but you may find either a little wetness and/or that pinkish staining in some form at some part of the lower edge. I had that on my D3 A8 W12 under warranty and only found it myself by chance during a close inspection like described. No drops ever hit ground.
iii. Pull off the plastic plenum covers--one one behind the motor in front of windshield. The HVAC filter is in the center of that cover area. Look down into it on the passenger side. That is where the heater control valve block is. It has a bunch of hoses clamped to it. Inspect that area carefully and again look for any pink residue. If it leaks there and doesn't evaporate, the coolant will go out toward the sides of the car underneath and could be missed. Mine also had a small leak there early on, but not enough to drip out the bottom.
3. The cooler. Below is a parts diagram showing it. The take off point for it is way back toward the rear of the transmission:
a. please confirm this is area mechanic pulled it from.
b. has any coolant line to it that was leaking been replaced, or is it still pending receiving the part?
c. was it confirmed to either not leak, or to leak internally--between the oil and the coolant? I would do that either by visual confirmation coolant was found on the "oil side" of that, and/or by pressure testing it.
While the parts description below says "gear oil cooler" for #9, it seems from the diagram like that is really the transmission area. It is not near either the mid (Torsen) differential which is at the extreme back of the tail of the transmission, nor the front differential that is a lot farther forward, and they don't have any fluid connections between the two that run inside the main transmission case. My W12 has coolers for both gear oil and transmission fluid and they are differently placed, so I can't be sure here. Maybe some other board member knows this set up on the later 4.2's? But, the failures I have ever read on this board for this part are approximately zero, and anything on the later motor's transmission even closer to zero. Nonelessless, from your first post about transmission shifting issues, it is critical to know if coolant was mixed with transmission fluid, and worth checking back with mechanics who helped you. Also important to know what fluid was on the "transmission side" of what they pulled out. A mechanic should know. If it was a differential related cooler, that oil invariably has a strong odor and smells almost rancid. Most any mechanic knows the smell. If transmission fluid, it is a light oil and sort of non descriptive; at your miles it will just be dark color or near black.
A hunch here is it really is a cooler on the transmission side given symptoms and the port take off locations in the parts diagram. That means the parts description itself is misleading; Audi does seem to say "oil" while we say "fluid" for transmissions too. This is where you need the hands on information to confirm. The cooler and related coolant hoses of course have to be in order in general. After all that, if it seems there was no evidence of coolant mixing, the fluid level needs to be properly checked. I don't get clear sense it has been filled to correct level, or at least I raise the question. Given all that has happened, probably a better plan is to drain the fluid, check for any contamination with coolant, and then replace if in order. Given is is easier on a 4.2 than my W12, I would replace the transmission filter at the same time. That means the transmission pan comes off, but also a chance to inspect. The service work and fluids will cost at least several hundred dollars to set expectations too; more if you use Audi or ZF branded fluids. If any contamination, the transmission needs to be flushed completely. I have no experience with that, and really seems like transmission shop expertise would be needed then. If no contamination, put new fluid in and set it to proper level using Audi/ZF procedure. They key part of that is it is set with the car level, engine running and at a pan/transmission oil temperature level of approx 40C.
1. The engine codes being there in earlier scans but then clearing with no work explained that should be affecting them is not making sense to me. Maybe a harness wire was disconnected at one point, or codes were not cleared from some old issues? In any case, as long as engine is running correctly, we can move past that. But, if not, work needs to stay focused there too to resolve.
2. The coolant leaking:
a. As another member mentioned, if the reservoir is leaking, it needs to be replaced. Does it have dripping or leaking?
b. Do a complete inspection again for coolant leaks, if you are saying it is still losing coolant. To be clear, are you saying coolant level still drops or not? Some incremental ideas:
i. In looking for leaks, look for any pink discoloration, slight pinking stains or fluffy pink powdery material. The pink comes from the coolant as it evaporates or burns off. If it is burning off, that would explain why you don't find it on the ground.
ii. Take the belly pan off under the motor and look there, both for leaks and for the stains. The top side of the cover is actually a simple great diagnostic tool if you just study what has landed on it over tens of thousands of miles. If you find anything, trace it back to source. In doing so, also look at front lower edge of radiator, and the part of the belly pan cover that comes near that area. If radiator has only a slight leak, ir will likely burn off/evaporate from the engine heat, but you may find either a little wetness and/or that pinkish staining in some form at some part of the lower edge. I had that on my D3 A8 W12 under warranty and only found it myself by chance during a close inspection like described. No drops ever hit ground.
iii. Pull off the plastic plenum covers--one one behind the motor in front of windshield. The HVAC filter is in the center of that cover area. Look down into it on the passenger side. That is where the heater control valve block is. It has a bunch of hoses clamped to it. Inspect that area carefully and again look for any pink residue. If it leaks there and doesn't evaporate, the coolant will go out toward the sides of the car underneath and could be missed. Mine also had a small leak there early on, but not enough to drip out the bottom.
3. The cooler. Below is a parts diagram showing it. The take off point for it is way back toward the rear of the transmission:
a. please confirm this is area mechanic pulled it from.
b. has any coolant line to it that was leaking been replaced, or is it still pending receiving the part?
c. was it confirmed to either not leak, or to leak internally--between the oil and the coolant? I would do that either by visual confirmation coolant was found on the "oil side" of that, and/or by pressure testing it.
While the parts description below says "gear oil cooler" for #9, it seems from the diagram like that is really the transmission area. It is not near either the mid (Torsen) differential which is at the extreme back of the tail of the transmission, nor the front differential that is a lot farther forward, and they don't have any fluid connections between the two that run inside the main transmission case. My W12 has coolers for both gear oil and transmission fluid and they are differently placed, so I can't be sure here. Maybe some other board member knows this set up on the later 4.2's? But, the failures I have ever read on this board for this part are approximately zero, and anything on the later motor's transmission even closer to zero. Nonelessless, from your first post about transmission shifting issues, it is critical to know if coolant was mixed with transmission fluid, and worth checking back with mechanics who helped you. Also important to know what fluid was on the "transmission side" of what they pulled out. A mechanic should know. If it was a differential related cooler, that oil invariably has a strong odor and smells almost rancid. Most any mechanic knows the smell. If transmission fluid, it is a light oil and sort of non descriptive; at your miles it will just be dark color or near black.
A hunch here is it really is a cooler on the transmission side given symptoms and the port take off locations in the parts diagram. That means the parts description itself is misleading; Audi does seem to say "oil" while we say "fluid" for transmissions too. This is where you need the hands on information to confirm. The cooler and related coolant hoses of course have to be in order in general. After all that, if it seems there was no evidence of coolant mixing, the fluid level needs to be properly checked. I don't get clear sense it has been filled to correct level, or at least I raise the question. Given all that has happened, probably a better plan is to drain the fluid, check for any contamination with coolant, and then replace if in order. Given is is easier on a 4.2 than my W12, I would replace the transmission filter at the same time. That means the transmission pan comes off, but also a chance to inspect. The service work and fluids will cost at least several hundred dollars to set expectations too; more if you use Audi or ZF branded fluids. If any contamination, the transmission needs to be flushed completely. I have no experience with that, and really seems like transmission shop expertise would be needed then. If no contamination, put new fluid in and set it to proper level using Audi/ZF procedure. They key part of that is it is set with the car level, engine running and at a pan/transmission oil temperature level of approx 40C.
Last edited by MP4.2+6.0; 12-10-2017 at 09:34 AM.
12-10-2017, 09:37 AM
#15
AudiWorld Super User
Also confirming as others have mentioned, I don't see any signs of issues with engine oil contamination. Thus my focus on transmission side from my long reply.
Last edited by MP4.2+6.0; 12-10-2017 at 09:39 AM.
12-10-2017, 09:50 AM
#16
AudiWorld Senior Member
See my much longer reply for more info, but FWIW your assumption is not necessarily true. If the leak is small, it may just burn off and evaporate with the engine heat. Read my long reply. Understanding the pink residue look and searching for it is critical when dealing with small leaks. Do NOT assume it will always be evidenced by something ending up on the ground or underneath.
Also confirming as others have mentioned, I don't see any signs of issues with engine oil contamination. Thus my focus on transmission side from my long reply.
Also confirming as others have mentioned, I don't see any signs of issues with engine oil contamination. Thus my focus on transmission side from my long reply.
My leaks on W12 never made it to the ground, pinholes in plastic coolant tubing, and a leaky hose at connection to plastic tube.
.
12-10-2017, 09:55 AM
#17
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Catching up, various reactions:
1. The engine codes being there in earlier scans but then clearing with no work explained that should be affecting them is not making sense to me. Maybe a harness wire was disconnected at one point, or codes were not cleared from some old issues? In any case, as long as engine is running correctly, we can move past that. But, if not, work needs to stay focused there too to resolve.
2. The coolant leaking:
a. As another member mentioned, if the reservoir is leaking, it needs to be replaced. Does it have dripping or leaking?
b. Do a complete inspection again for coolant leaks, if you are saying it is still losing coolant. To be clear, are you saying coolant level still drops or not? Some incremental ideas:
i. In looking for leaks, look for any pink discoloration, slight pinking stains or fluffy pink powdery material. The pink comes from the coolant as it evaporates or burns off. If it is burning off, that would explain why you don't find it on the ground.
ii. Take the belly pan off under the motor and look there, both for leaks and for the stains. The top side of the cover is actually a simple great diagnostic tool if you just study what has landed on it over tens of thousands of miles. If you find anything, trace it back to source. In doing so, also look at front lower edge of radiator, and the part of the belly pan cover that comes near that area. If radiator has only a slight leak, ir will likely burn off/evaporate from the engine heat, but you may find either a little wetness and/or that pinkish staining in some form at some part of the lower edge. I had that on my D3 A8 W12 under warranty and only found it myself by chance during a close inspection like described. No drops ever hit ground.
iii. Pull off the plastic plenum covers--one one behind the motor in front of windshield. The HVAC filter is in the center of that cover area. Look down into it on the passenger side. That is where the heater control valve block is. It has a bunch of hoses clamped to it. Inspect that area carefully and again look for any pink residue. If it leaks there and doesn't evaporate, the coolant will go out toward the sides of the car underneath and could be missed. Mine also had a small leak there early on, but not enough to drip out the bottom.
3. The cooler. Below is a parts diagram showing it. The take off point for it is way back toward the rear of the transmission:
a. please confirm this is area mechanic pulled it from.
b. has any coolant line to it that was leaking been replaced, or is it still pending receiving the part?
c. was it confirmed to either not leak, or to leak internally--between the oil and the coolant? I would do that either by visual confirmation coolant was found on the "oil side" of that, and/or by pressure testing it.
While the parts description below says "gear oil cooler" for #9, it seems from the diagram like that is really the transmission area. It is not near either the mid (Torsen) differential which is at the extreme back of the tail of the transmission, nor the front differential that is a lot farther forward, and they don't have any fluid connections between the two that run inside the main transmission case. My W12 has coolers for both gear oil and transmission fluid and they are differently placed, so I can't be sure here. Maybe some other board member knows this set up on the later 4.2's? But, the failures I have ever read on this board for this part are approximately zero, and anything on the later motor's transmission even closer to zero. Nonelessless, from your first post about transmission shifting issues, it is critical to know if coolant was mixed with transmission fluid, and worth checking back with mechanics who helped you. Also important to know what fluid was on the "transmission side" of what they pulled out. A mechanic should know. If it was a differential related cooler, that oil invariably has a strong odor and smells almost rancid. Most any mechanic knows the smell. If transmission fluid, it is a light oil and sort of non descriptive; at your miles it will just be dark color or near black.
A hunch here is it really is a cooler on the transmission side given symptoms and the port take off locations in the parts diagram. That means the parts description itself is misleading; Audi does seem to say "oil" while we say "fluid" for transmissions too. This is where you need the hands on information to confirm. The cooler and related coolant hoses of course have to be in order in general. After all that, if it seems there was no evidence of coolant mixing, the fluid level needs to be properly checked. I don't get clear sense it has been filled to correct level, or at least I raise the question. Given all that has happened, probably a better plan is to drain the fluid, check for any contamination with coolant, and then replace if in order. Given is is easier on a 4.2 than my W12, I would replace the transmission filter at the same time. That means the transmission pan comes off, but also a chance to inspect. The service work and fluids will cost at least several hundred dollars to set expectations too; more if you use Audi or ZF branded fluids. If any contamination, the transmission needs to be flushed completely. I have no experience with that, and really seems like transmission shop expertise would be needed then. If no contamination, put new fluid in and set it to proper level using Audi/ZF procedure. They key part of that is it is set with the car level, engine running and at a pan/transmission oil temperature level of approx 40C.
1. The engine codes being there in earlier scans but then clearing with no work explained that should be affecting them is not making sense to me. Maybe a harness wire was disconnected at one point, or codes were not cleared from some old issues? In any case, as long as engine is running correctly, we can move past that. But, if not, work needs to stay focused there too to resolve.
2. The coolant leaking:
a. As another member mentioned, if the reservoir is leaking, it needs to be replaced. Does it have dripping or leaking?
b. Do a complete inspection again for coolant leaks, if you are saying it is still losing coolant. To be clear, are you saying coolant level still drops or not? Some incremental ideas:
i. In looking for leaks, look for any pink discoloration, slight pinking stains or fluffy pink powdery material. The pink comes from the coolant as it evaporates or burns off. If it is burning off, that would explain why you don't find it on the ground.
ii. Take the belly pan off under the motor and look there, both for leaks and for the stains. The top side of the cover is actually a simple great diagnostic tool if you just study what has landed on it over tens of thousands of miles. If you find anything, trace it back to source. In doing so, also look at front lower edge of radiator, and the part of the belly pan cover that comes near that area. If radiator has only a slight leak, ir will likely burn off/evaporate from the engine heat, but you may find either a little wetness and/or that pinkish staining in some form at some part of the lower edge. I had that on my D3 A8 W12 under warranty and only found it myself by chance during a close inspection like described. No drops ever hit ground.
iii. Pull off the plastic plenum covers--one one behind the motor in front of windshield. The HVAC filter is in the center of that cover area. Look down into it on the passenger side. That is where the heater control valve block is. It has a bunch of hoses clamped to it. Inspect that area carefully and again look for any pink residue. If it leaks there and doesn't evaporate, the coolant will go out toward the sides of the car underneath and could be missed. Mine also had a small leak there early on, but not enough to drip out the bottom.
3. The cooler. Below is a parts diagram showing it. The take off point for it is way back toward the rear of the transmission:
a. please confirm this is area mechanic pulled it from.
b. has any coolant line to it that was leaking been replaced, or is it still pending receiving the part?
c. was it confirmed to either not leak, or to leak internally--between the oil and the coolant? I would do that either by visual confirmation coolant was found on the "oil side" of that, and/or by pressure testing it.
While the parts description below says "gear oil cooler" for #9, it seems from the diagram like that is really the transmission area. It is not near either the mid (Torsen) differential which is at the extreme back of the tail of the transmission, nor the front differential that is a lot farther forward, and they don't have any fluid connections between the two that run inside the main transmission case. My W12 has coolers for both gear oil and transmission fluid and they are differently placed, so I can't be sure here. Maybe some other board member knows this set up on the later 4.2's? But, the failures I have ever read on this board for this part are approximately zero, and anything on the later motor's transmission even closer to zero. Nonelessless, from your first post about transmission shifting issues, it is critical to know if coolant was mixed with transmission fluid, and worth checking back with mechanics who helped you. Also important to know what fluid was on the "transmission side" of what they pulled out. A mechanic should know. If it was a differential related cooler, that oil invariably has a strong odor and smells almost rancid. Most any mechanic knows the smell. If transmission fluid, it is a light oil and sort of non descriptive; at your miles it will just be dark color or near black.
A hunch here is it really is a cooler on the transmission side given symptoms and the port take off locations in the parts diagram. That means the parts description itself is misleading; Audi does seem to say "oil" while we say "fluid" for transmissions too. This is where you need the hands on information to confirm. The cooler and related coolant hoses of course have to be in order in general. After all that, if it seems there was no evidence of coolant mixing, the fluid level needs to be properly checked. I don't get clear sense it has been filled to correct level, or at least I raise the question. Given all that has happened, probably a better plan is to drain the fluid, check for any contamination with coolant, and then replace if in order. Given is is easier on a 4.2 than my W12, I would replace the transmission filter at the same time. That means the transmission pan comes off, but also a chance to inspect. The service work and fluids will cost at least several hundred dollars to set expectations too; more if you use Audi or ZF branded fluids. If any contamination, the transmission needs to be flushed completely. I have no experience with that, and really seems like transmission shop expertise would be needed then. If no contamination, put new fluid in and set it to proper level using Audi/ZF procedure. They key part of that is it is set with the car level, engine running and at a pan/transmission oil temperature level of approx 40C.
I will start with trying to get to the bottom of the problem of the missing coolant as it will give me some peace of mind that there are no mixing of oil and coolant .
in my first post I wrote about all the work I did on the engine before clearing the fault codes
and about the location of the cooler yes I saw him installing it there here is another diagram
I will keep updating of the progress
Thank you all again
12-10-2017, 10:04 AM
#18
AudiWorld Super User
Also confirming GG's posts with the pictures of coolant burn off are the sort of thing you are looking for. It may have the pinkish tinge as mentioned, may be more tan or white, and may be in any of oily, crusty or powdery type forms.
Here is another pic. from the web of a different vehicle with the sort of stuff to look for when it gets bad. This is the crusty type look. With a pinhole leak under pressure and pointed sideways or upward, you can end up with the fluffy type stuff instead.
Here is another pic. from the web of a different vehicle with the sort of stuff to look for when it gets bad. This is the crusty type look. With a pinhole leak under pressure and pointed sideways or upward, you can end up with the fluffy type stuff instead.
Last edited by MP4.2+6.0; 12-10-2017 at 11:00 AM.
12-10-2017, 10:46 AM
#19
AudiWorld Super User
Given newest reply, I am still concerned about trying to sort out what is "history" and what is "current."
1. I take it that what is still still current is that you are detecting a loss of coolant over time at the coolant reservoir, correct? Just to tie off, are you checking it in consistent way, basically fully engine cold, preferably overnight, and on the same ground level wise? If it is minor/slow, sometimes I mark bottle with a pencil or Sharpie to watch it over lime and have no doubt about prior level observed.
2. Is there a current transmission shifting issue, or is that historical? I think that is current, hence focus there.
FWIW, AFAIK and to tie it off, there is NO intersection between the engine oil type issues and the transmission behavior, unless engine is basically at point of breaking. Yes, watch for coolant mixing with engine oil, but that seems confirmed as not the case. FWIW, some people refer to the transmission lubricant as oil (including Audi and ZF I think), though many posters here and me would call it transmission fluid and the usual abbreviation is ATF. With the discussion crossing all of transmission, engine and "gear oil cooler" I want to be sure we are on same page about the different elements.
Meantime, simplified at engine and transmission intersections of behavior that are relevant (as in, not the engine oil), the electrical and electronic side are interconnected. Thus, if a connector or wire gets messed up during repair work or is left disconnected, that of course can create issues. If it gets fixed or plugged back in, the codes probably remain until cleared even if issue resolves. The MAF codes and the speed related sensor signal were both some clues that do bear on key inputs transmission computer uses (either received directly or via the engine computer) to decide on shifting. Hence my points there, but now I also want to be doubly sure any elements being discussed are current issues and not just historical. If shifting behavior is a current issue and there are no codes, the simplest and most likely scenario is the fluid level is wrong. It can end up with codes as fluid level gets way off, but earlier on you may start to notice shifting oddities. Meantime, you do want to get the coolant leak straightened out, and be 100% sure there was no fluid cross contamination between the coolant and the ATF.
1. I take it that what is still still current is that you are detecting a loss of coolant over time at the coolant reservoir, correct? Just to tie off, are you checking it in consistent way, basically fully engine cold, preferably overnight, and on the same ground level wise? If it is minor/slow, sometimes I mark bottle with a pencil or Sharpie to watch it over lime and have no doubt about prior level observed.
2. Is there a current transmission shifting issue, or is that historical? I think that is current, hence focus there.
FWIW, AFAIK and to tie it off, there is NO intersection between the engine oil type issues and the transmission behavior, unless engine is basically at point of breaking. Yes, watch for coolant mixing with engine oil, but that seems confirmed as not the case. FWIW, some people refer to the transmission lubricant as oil (including Audi and ZF I think), though many posters here and me would call it transmission fluid and the usual abbreviation is ATF. With the discussion crossing all of transmission, engine and "gear oil cooler" I want to be sure we are on same page about the different elements.
Meantime, simplified at engine and transmission intersections of behavior that are relevant (as in, not the engine oil), the electrical and electronic side are interconnected. Thus, if a connector or wire gets messed up during repair work or is left disconnected, that of course can create issues. If it gets fixed or plugged back in, the codes probably remain until cleared even if issue resolves. The MAF codes and the speed related sensor signal were both some clues that do bear on key inputs transmission computer uses (either received directly or via the engine computer) to decide on shifting. Hence my points there, but now I also want to be doubly sure any elements being discussed are current issues and not just historical. If shifting behavior is a current issue and there are no codes, the simplest and most likely scenario is the fluid level is wrong. It can end up with codes as fluid level gets way off, but earlier on you may start to notice shifting oddities. Meantime, you do want to get the coolant leak straightened out, and be 100% sure there was no fluid cross contamination between the coolant and the ATF.
Last edited by MP4.2+6.0; 12-10-2017 at 10:59 AM.
12-10-2017, 11:28 AM
#20
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Given newest reply, I am still concerned about trying to sort out what is "history" and what is "current."
1. I take it that what is still still current is that you are detecting a loss of coolant over time at the coolant reservoir, correct? Just to tie off, are you checking it in consistent way, basically fully engine cold, preferably overnight, and on the same ground level wise? If it is minor/slow, sometimes I mark bottle with a pencil or Sharpie to watch it over lime and have no doubt about prior level observed.
2. Is there a current transmission shifting issue, or is that historical? I think that is current, hence focus there.
FWIW, AFAIK and to tie it off, there is NO intersection between the engine oil type issues and the transmission behavior, unless engine is basically at point of breaking. Yes, watch for coolant mixing with engine oil, but that seems confirmed as not the case. FWIW, some people refer to the transmission lubricant as oil (including Audi and ZF I think), though many posters here and me would call it transmission fluid and the usual abbreviation is ATF. With the discussion crossing all of transmission, engine and "gear oil cooler" I want to be sure we are on same page about the different elements.
Meantime, simplified at engine and transmission intersections of behavior that are relevant (as in, not the engine oil), the electrical and electronic side are interconnected. Thus, if a connector or wire gets messed up during repair work or is left disconnected, that of course can create issues. If it gets fixed or plugged back in, the codes probably remain until cleared even if issue resolves. The MAF codes and the speed related signal were both some clues that do bear on key inputs transmission computer uses (either received directly or via the engine computer to decide on shifting. Hence my points there, but now I also want to be doubly sure they are current issues and not just historical. If they are current and there are no codes, the simplest and most likely scenario is the fluid level is wrong. But you do want to get the coolant leak straightened out, and be 100% sure there was no fluid cross contamination between the coolant and the ATF.
1. I take it that what is still still current is that you are detecting a loss of coolant over time at the coolant reservoir, correct? Just to tie off, are you checking it in consistent way, basically fully engine cold, preferably overnight, and on the same ground level wise? If it is minor/slow, sometimes I mark bottle with a pencil or Sharpie to watch it over lime and have no doubt about prior level observed.
2. Is there a current transmission shifting issue, or is that historical? I think that is current, hence focus there.
FWIW, AFAIK and to tie it off, there is NO intersection between the engine oil type issues and the transmission behavior, unless engine is basically at point of breaking. Yes, watch for coolant mixing with engine oil, but that seems confirmed as not the case. FWIW, some people refer to the transmission lubricant as oil (including Audi and ZF I think), though many posters here and me would call it transmission fluid and the usual abbreviation is ATF. With the discussion crossing all of transmission, engine and "gear oil cooler" I want to be sure we are on same page about the different elements.
Meantime, simplified at engine and transmission intersections of behavior that are relevant (as in, not the engine oil), the electrical and electronic side are interconnected. Thus, if a connector or wire gets messed up during repair work or is left disconnected, that of course can create issues. If it gets fixed or plugged back in, the codes probably remain until cleared even if issue resolves. The MAF codes and the speed related signal were both some clues that do bear on key inputs transmission computer uses (either received directly or via the engine computer to decide on shifting. Hence my points there, but now I also want to be doubly sure they are current issues and not just historical. If they are current and there are no codes, the simplest and most likely scenario is the fluid level is wrong. But you do want to get the coolant leak straightened out, and be 100% sure there was no fluid cross contamination between the coolant and the ATF.
I was concern that my first post was too long and confusing, but the intention was to give the background picture that lead to this point, as I try to trace back to the point where the faults started and bring the car to that point . it was long and with a lot of information :-)
This is where I stand now:
engine working smooth no fault codes
coolant continue under investigation and always checked on flat surface and cold
Transmission still give problems the last time I tried adaption after clearing all faults on engine
the best way to describe it is from a manual gear shift, when you stay in 4th or 5th gear slow down when you get to the intersection forget to lower to 3rd or 2nd gear and try to accelerate again in 4th the car start to shake, and this is how my transmission behave it doesn't shift down unless I press the brake pedal, from your other reply I understood that the ECM communicate with the TCM that's why I centered my attention on
fixing the engine faults and tried adaption
and still.....