2001 A8L - Transmission Problems (among others)
11-24-2015, 08:22 AM
#1
AudiWorld Junior Member
Thread Starter
2001 A8L - Transmission Problems (among others)
Well as this is my first post, I'd like to say greetings to the AudiWorld community, I'm glad to have become a member. Now onto my reason for this post. (I apologize beforehand for the length)
In May 2015 I bought a 2001 A8L with 202k miles as my first car. It was in pretty rough shape when I got it but I've turned it around for the most part. The guy who had it before me had put in Autolite spark plugs and green coolant for God's sake... Anyway I did a regular tune-up, which consisted of a full synthetic oil change, new Bosch spark plugs, new front pads and rotors (rear were brand new), new intake and cabin air filters, took out all the small braided vacuum lines which were frayed and installed new ones, cleared out the AC evap drains, topped off all fluids, then did a meticulous detailing of the entire car. Since the day I got it there has been a slow coolant leak that I cannot locate, the warning light for low coolant comes on every 3 days or so and I have to top it off and repeat the process. 2 months after I bought it, (and 8k miles later) I noticed that it started to overheat so by doing some reading in the forums I concluded that the thermostat had gone bad. I went to my cousin's shop and proceeded to do the job myself with a new thermostat and enough G12 coolant for a coolant flush (still had green coolant) by the help of dognmonkey's tutorial.... without a cam lock bar. I also forgot to at least zip tie the cam sprockets so they wouldn't move but anyway by forgetting that, I ended up throwing the timing a tooth off. It has never been right since then, I have tried to reset the timing about 4 ties now along with the cam lock bar but the least I have got it down to is about 1/2 tooth, which is how I currently drive it until I figure out how to set the timing correctly. Another problem I have is the right rear spring which the lowermost part that sits on the rubber bushing had snapped when I did the left rear wheel bearing, so this now causes the car to sit about 1 inch lower in the right rear, and now the left front tire is starting to wear on the inside. Next problem is with the Secondary Air Injection system, almost every time the car is started the system runs for about 30 seconds and causes the engine to run extremely rough until the pump shuts off. I suspect that the kombi valves have built up carbon not only due to the age and mileage of the car, but also that I drive the car with the timing off 1/2 tooth. I'm contemplating on whether to just do an SAI delete or try to attempt to clean out the kombi valves.
And now onto the transmission.
As this was my first car I did what a normal teenager does and immediately recoded the transmission to the sport setting and started racing my friends ('03 S8 ftw), doing hard launches off the line, etc. But inevitably that wore off and I started to drive the car normally and I noticed that there was a whine while the car is in first gear, almost sounding like a supercharger whine. Shifts fine, no slip at all, but on occasion the downshifts will be just a tad rough but I think that might be due to the trans/engine mounts (front engine mount by oil cooler is shot). Scanned the car and a code came up saying "Torque Converter Clutch Stuck OFF". I raised the car up and noticed that there was some residue at the point where the driveshaft meets the transmission, so I concluded that the output shaft seal had gone bad and I was getting low on fluid which in turn causes the transmission to be jerky. But then after doing some reading on the forums I saw that the output shaft uses gear oil instead of the transmission fluid... So I'm stuck clueless. My friend's S8 transmission recently went bad on him, it went into limp mode and if he tries to drive it the trans will slip, so we're 90% sure that the torque converter is toast as he was also low on trans fluid. My A8 currently has 213k miles. Anyone have an idea what could be wrong with mine? Any help greatly appreciated!
*I have also posted this in the Audizine forums to gather as many opinions as possible*
In May 2015 I bought a 2001 A8L with 202k miles as my first car. It was in pretty rough shape when I got it but I've turned it around for the most part. The guy who had it before me had put in Autolite spark plugs and green coolant for God's sake... Anyway I did a regular tune-up, which consisted of a full synthetic oil change, new Bosch spark plugs, new front pads and rotors (rear were brand new), new intake and cabin air filters, took out all the small braided vacuum lines which were frayed and installed new ones, cleared out the AC evap drains, topped off all fluids, then did a meticulous detailing of the entire car. Since the day I got it there has been a slow coolant leak that I cannot locate, the warning light for low coolant comes on every 3 days or so and I have to top it off and repeat the process. 2 months after I bought it, (and 8k miles later) I noticed that it started to overheat so by doing some reading in the forums I concluded that the thermostat had gone bad. I went to my cousin's shop and proceeded to do the job myself with a new thermostat and enough G12 coolant for a coolant flush (still had green coolant) by the help of dognmonkey's tutorial.... without a cam lock bar. I also forgot to at least zip tie the cam sprockets so they wouldn't move but anyway by forgetting that, I ended up throwing the timing a tooth off. It has never been right since then, I have tried to reset the timing about 4 ties now along with the cam lock bar but the least I have got it down to is about 1/2 tooth, which is how I currently drive it until I figure out how to set the timing correctly. Another problem I have is the right rear spring which the lowermost part that sits on the rubber bushing had snapped when I did the left rear wheel bearing, so this now causes the car to sit about 1 inch lower in the right rear, and now the left front tire is starting to wear on the inside. Next problem is with the Secondary Air Injection system, almost every time the car is started the system runs for about 30 seconds and causes the engine to run extremely rough until the pump shuts off. I suspect that the kombi valves have built up carbon not only due to the age and mileage of the car, but also that I drive the car with the timing off 1/2 tooth. I'm contemplating on whether to just do an SAI delete or try to attempt to clean out the kombi valves.
And now onto the transmission.
As this was my first car I did what a normal teenager does and immediately recoded the transmission to the sport setting and started racing my friends ('03 S8 ftw), doing hard launches off the line, etc. But inevitably that wore off and I started to drive the car normally and I noticed that there was a whine while the car is in first gear, almost sounding like a supercharger whine. Shifts fine, no slip at all, but on occasion the downshifts will be just a tad rough but I think that might be due to the trans/engine mounts (front engine mount by oil cooler is shot). Scanned the car and a code came up saying "Torque Converter Clutch Stuck OFF". I raised the car up and noticed that there was some residue at the point where the driveshaft meets the transmission, so I concluded that the output shaft seal had gone bad and I was getting low on fluid which in turn causes the transmission to be jerky. But then after doing some reading on the forums I saw that the output shaft uses gear oil instead of the transmission fluid... So I'm stuck clueless. My friend's S8 transmission recently went bad on him, it went into limp mode and if he tries to drive it the trans will slip, so we're 90% sure that the torque converter is toast as he was also low on trans fluid. My A8 currently has 213k miles. Anyone have an idea what could be wrong with mine? Any help greatly appreciated!
*I have also posted this in the Audizine forums to gather as many opinions as possible*
11-25-2015, 09:20 AM
#2
AudiWorld Member
Personally, pony up the money to buy or rent one from Blauparts.com I can't emphasize enough how critical getting the cams and crank synced properly. You also need a crank lock pin too. You remove a plug on the driver's side of the block and lock the crank in TDC while you set timing belt tension. Do you have access to a Bentley manual or AllData? There is a whole procedure for performing this correctly. Personally, it's not something I would leave to chance.
The Transmission is a ZF 5HP24A (A for all wheel drive), and this transmission is known for having problems in the valve body with one of the pressure spools. Audi A8 Quattro ZF5HP24 TCC Cycling Bang - Sonnax Part of the valve body itself can develop a stress crack and leak pressure thereby changing shift points and causing clunks.
Also, the transmission is known for wearing out a thrust bearing located immediately behind the most FWD clutch drum. ZF 5HP24 teardown - Page 2
This causes parts to "sag" and prematurely tearing an o-ring which will lead to loss of certain gears. The torque converter is known for wearing out the clutch lining and has to be cut apart to replace the lining. Remanufactured torque converters are not available for any kind of reasonable price. They can be rebuilt for about $300. Check with Eriksson Industries in Old Saybrook CT, they are a Certified ZF distributor.
I'm sure others will chime in, but this is a start. You have an A8, prepare to get a second job to pay for parts. It's not going to be cheap!
And now onto the transmission.
As this was my first car I did what a normal teenager does and immediately recoded the transmission to the sport setting and started racing my friends ('03 S8 ftw), doing hard launches off the line, etc. But inevitably that wore off and I started to drive the car normally and I noticed that there was a whine while the car is in first gear, almost sounding like a supercharger whine. Shifts fine, no slip at all, but on occasion the downshifts will be just a tad rough but I think that might be due to the trans/engine mounts (front engine mount by oil cooler is shot). Scanned the car and a code came up saying "Torque Converter Clutch Stuck OFF". I raised the car up and noticed that there was some residue at the point where the driveshaft meets the transmission, so I concluded that the output shaft seal had gone bad and I was getting low on fluid which in turn causes the transmission to be jerky. But then after doing some reading on the forums I saw that the output shaft uses gear oil instead of the transmission fluid... So I'm stuck clueless. My friend's S8 transmission recently went bad on him, it went into limp mode and if he tries to drive it the trans will slip, so we're 90% sure that the torque converter is toast as he was also low on trans fluid. My A8 currently has 213k miles. Anyone have an idea what could be wrong with mine? Any help greatly appreciated!
As this was my first car I did what a normal teenager does and immediately recoded the transmission to the sport setting and started racing my friends ('03 S8 ftw), doing hard launches off the line, etc. But inevitably that wore off and I started to drive the car normally and I noticed that there was a whine while the car is in first gear, almost sounding like a supercharger whine. Shifts fine, no slip at all, but on occasion the downshifts will be just a tad rough but I think that might be due to the trans/engine mounts (front engine mount by oil cooler is shot). Scanned the car and a code came up saying "Torque Converter Clutch Stuck OFF". I raised the car up and noticed that there was some residue at the point where the driveshaft meets the transmission, so I concluded that the output shaft seal had gone bad and I was getting low on fluid which in turn causes the transmission to be jerky. But then after doing some reading on the forums I saw that the output shaft uses gear oil instead of the transmission fluid... So I'm stuck clueless. My friend's S8 transmission recently went bad on him, it went into limp mode and if he tries to drive it the trans will slip, so we're 90% sure that the torque converter is toast as he was also low on trans fluid. My A8 currently has 213k miles. Anyone have an idea what could be wrong with mine? Any help greatly appreciated!
Also, the transmission is known for wearing out a thrust bearing located immediately behind the most FWD clutch drum. ZF 5HP24 teardown - Page 2
This causes parts to "sag" and prematurely tearing an o-ring which will lead to loss of certain gears. The torque converter is known for wearing out the clutch lining and has to be cut apart to replace the lining. Remanufactured torque converters are not available for any kind of reasonable price. They can be rebuilt for about $300. Check with Eriksson Industries in Old Saybrook CT, they are a Certified ZF distributor.
I'm sure others will chime in, but this is a start. You have an A8, prepare to get a second job to pay for parts. It's not going to be cheap!
11-25-2015, 01:22 PM
#3
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For your coolant leak, I'd take a look at the bleeder screw housings.
They are made of reinforced plastic and have a tenancy to age and crack along the mould line - especially if screw type hose clamps have replaced the spring clamps on either side of the housings (mechanics can tighten these too much (they're plastic...)).
The cracks can be hairline and the only giveaway will be an occasional drip from one of the hoses once warmed up.
Mine gave itself away by dripping onto the exhaust manifold when I shut her down.
Be aware - they don't repair well (I tried the powder and superglue stuff) and they're $50 ea as a dealer only part.
...Should get Gruven to make Aluminium housings for replacement!
They are made of reinforced plastic and have a tenancy to age and crack along the mould line - especially if screw type hose clamps have replaced the spring clamps on either side of the housings (mechanics can tighten these too much (they're plastic...)).
The cracks can be hairline and the only giveaway will be an occasional drip from one of the hoses once warmed up.
Mine gave itself away by dripping onto the exhaust manifold when I shut her down.
Be aware - they don't repair well (I tried the powder and superglue stuff) and they're $50 ea as a dealer only part.
...Should get Gruven to make Aluminium housings for replacement!
Last edited by twentysevenlitres; 11-25-2015 at 01:29 PM.
11-30-2015, 03:31 AM
#4
AudiWorld Junior Member
Thread Starter
For your coolant leak, I'd take a look at the bleeder screw housings.
They are made of reinforced plastic and have a tenancy to age and crack along the mould line - especially if screw type hose clamps have replaced the spring clamps on either side of the housings (mechanics can tighten these too much (they're plastic...)).
The cracks can be hairline and the only giveaway will be an occasional drip from one of the hoses once warmed up.
Mine gave itself away by dripping onto the exhaust manifold when I shut her down.
Be aware - they don't repair well (I tried the powder and superglue stuff) and they're $50 ea as a dealer only part.
...Should get Gruven to make Aluminium housings for replacement!
They are made of reinforced plastic and have a tenancy to age and crack along the mould line - especially if screw type hose clamps have replaced the spring clamps on either side of the housings (mechanics can tighten these too much (they're plastic...)).
The cracks can be hairline and the only giveaway will be an occasional drip from one of the hoses once warmed up.
Mine gave itself away by dripping onto the exhaust manifold when I shut her down.
Be aware - they don't repair well (I tried the powder and superglue stuff) and they're $50 ea as a dealer only part.
...Should get Gruven to make Aluminium housings for replacement!
11-30-2015, 03:38 AM
#5
AudiWorld Junior Member
Thread Starter
Personally, pony up the money to buy or rent one from Blauparts.com I can't emphasize enough how critical getting the cams and crank synced properly. You also need a crank lock pin too. You remove a plug on the driver's side of the block and lock the crank in TDC while you set timing belt tension. Do you have access to a Bentley manual or AllData? There is a whole procedure for performing this correctly. Personally, it's not something I would leave to chance.
The Transmission is a ZF 5HP24A (A for all wheel drive), and this transmission is known for having problems in the valve body with one of the pressure spools. Audi A8 Quattro ZF5HP24 TCC Cycling Bang - Sonnax Part of the valve body itself can develop a stress crack and leak pressure thereby changing shift points and causing clunks.
Also, the transmission is known for wearing out a thrust bearing located immediately behind the most FWD clutch drum. ZF 5HP24 teardown - Page 2
This causes parts to "sag" and prematurely tearing an o-ring which will lead to loss of certain gears. The torque converter is known for wearing out the clutch lining and has to be cut apart to replace the lining. Remanufactured torque converters are not available for any kind of reasonable price. They can be rebuilt for about $300. Check with Eriksson Industries in Old Saybrook CT, they are a Certified ZF distributor.
I'm sure others will chime in, but this is a start. You have an A8, prepare to get a second job to pay for parts. It's not going to be cheap!
The Transmission is a ZF 5HP24A (A for all wheel drive), and this transmission is known for having problems in the valve body with one of the pressure spools. Audi A8 Quattro ZF5HP24 TCC Cycling Bang - Sonnax Part of the valve body itself can develop a stress crack and leak pressure thereby changing shift points and causing clunks.
Also, the transmission is known for wearing out a thrust bearing located immediately behind the most FWD clutch drum. ZF 5HP24 teardown - Page 2
This causes parts to "sag" and prematurely tearing an o-ring which will lead to loss of certain gears. The torque converter is known for wearing out the clutch lining and has to be cut apart to replace the lining. Remanufactured torque converters are not available for any kind of reasonable price. They can be rebuilt for about $300. Check with Eriksson Industries in Old Saybrook CT, they are a Certified ZF distributor.
I'm sure others will chime in, but this is a start. You have an A8, prepare to get a second job to pay for parts. It's not going to be cheap!
12-07-2015, 07:25 AM
#7
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I remember something similar to your torque converter code when l had my 2.7 A6. There was a bad solenoid in the trans valve body. I think my code read something like "Torque Converter Circuit Open/Short To Ground". But mine would go into limp mode religiously, after a short drive.... Sorry, that may not be any help to you.
Regarding the occasionally rough shift I would first check your transmission fluid level to ensure you have the correct level; search on this forum for the correct procedure. ZF says you should change the fluid every 60k.
For the whining noise it makes me think of my dads 96 A6. It also has a whine, he's pretty sure it is due to being run while low on gear lube. He added gear lube but the whine was still there. Sounds like you may have the same issue
If those are the only issues you're having IMHO I don't believe you need to rebuild your transmission, but for sure Tozo could help you diagnose it.
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12-09-2015, 03:34 PM
#8
I suppose this could be true, but l personally think it's more of a stereotype, or a syndrome caused from always using the dealership lol.
I remember something similar to your torque converter code when l had my 2.7 A6. There was a bad solenoid in the trans valve body. I think my code read something like "Torque Converter Circuit Open/Short To Ground". But mine would go into limp mode religiously, after a short drive.... Sorry, that may not be any help to you.
Regarding the occasionally rough shift I would first check your transmission fluid level to ensure you have the correct level; search on this forum for the correct procedure. ZF says you should change the fluid every 60k.
For the whining noise it makes me think of my dads 96 A6. It also has a whine, he's pretty sure it is due to being run while low on gear lube. He added gear lube but the whine was still there. Sounds like you may have the same issue
If those are the only issues you're having IMHO I don't believe you need to rebuild your transmission, but for sure Tozo could help you diagnose it.
I remember something similar to your torque converter code when l had my 2.7 A6. There was a bad solenoid in the trans valve body. I think my code read something like "Torque Converter Circuit Open/Short To Ground". But mine would go into limp mode religiously, after a short drive.... Sorry, that may not be any help to you.
Regarding the occasionally rough shift I would first check your transmission fluid level to ensure you have the correct level; search on this forum for the correct procedure. ZF says you should change the fluid every 60k.
For the whining noise it makes me think of my dads 96 A6. It also has a whine, he's pretty sure it is due to being run while low on gear lube. He added gear lube but the whine was still there. Sounds like you may have the same issue
If those are the only issues you're having IMHO I don't believe you need to rebuild your transmission, but for sure Tozo could help you diagnose it.
usually the drum fails inside the trans requiring a full rebuild to fix it properly.
Sound like he might have something else going on but at his mileage it is overdue for a rebuild.
Either way you CAN buy CHEAP parts for an a8, but the fact of the matter is they won't last.
I've replaced 2 waterpumps with less than 30k miles on them because the previous shop/owner didn't buy a genuine audi waterpump.
So do you want to do the job twice? I certainly don't.
-Richard
Last edited by audinutt; 12-09-2015 at 03:39 PM.
12-12-2015, 06:48 PM
#9
AudiWorld Junior Member
Thread Starter
I suppose this could be true, but l personally think it's more of a stereotype, or a syndrome caused from always using the dealership lol.
I remember something similar to your torque converter code when l had my 2.7 A6. There was a bad solenoid in the trans valve body. I think my code read something like "Torque Converter Circuit Open/Short To Ground". But mine would go into limp mode religiously, after a short drive.... Sorry, that may not be any help to you.
Regarding the occasionally rough shift I would first check your transmission fluid level to ensure you have the correct level; search on this forum for the correct procedure. ZF says you should change the fluid every 60k.
For the whining noise it makes me think of my dads 96 A6. It also has a whine, he's pretty sure it is due to being run while low on gear lube. He added gear lube but the whine was still there. Sounds like you may have the same issue
If those are the only issues you're having IMHO I don't believe you need to rebuild your transmission, but for sure Tozo could help you diagnose it.
I remember something similar to your torque converter code when l had my 2.7 A6. There was a bad solenoid in the trans valve body. I think my code read something like "Torque Converter Circuit Open/Short To Ground". But mine would go into limp mode religiously, after a short drive.... Sorry, that may not be any help to you.
Regarding the occasionally rough shift I would first check your transmission fluid level to ensure you have the correct level; search on this forum for the correct procedure. ZF says you should change the fluid every 60k.
For the whining noise it makes me think of my dads 96 A6. It also has a whine, he's pretty sure it is due to being run while low on gear lube. He added gear lube but the whine was still there. Sounds like you may have the same issue
If those are the only issues you're having IMHO I don't believe you need to rebuild your transmission, but for sure Tozo could help you diagnose it.
Tozo actually did offer to help me but he asked for a vag-com report to see what's going on and I don't have vag-com yet...
As for the whining, when I change the driveshaft flange seal I'll be topping it up with gear oil, hope that fixes the whining...
And also for the torque converter code, I'm really not sure what it could be because the symptoms I get aren't persistent; just random. When I get ahold of vag-com I'll look into it though.
Speaking of vag-com, I found something on eBay from a seller in Bulgaria for $80 and it seems to be legit... any opinions?
HQ Pro VAG com VCDS Hex Can USB Diagnostic Tool Audi VW Seat VAG com Bus Coding | eBay
12-13-2015, 04:24 AM
#10
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Speaking of vag-com, I found something on eBay from a seller in Bulgaria for $80 and it seems to be legit... any opinions?
HQ Pro VAG com VCDS Hex Can USB Diagnostic Tool Audi VW Seat VAG com Bus Coding | eBay
HQ Pro VAG com VCDS Hex Can USB Diagnostic Tool Audi VW Seat VAG com Bus Coding | eBay
and for VAG-COM specifically $20
VAG com USB KKL 409 1 Cable for Audi VW OBD2 OBD 2 | eBay
I'd probably go with the latter.
And if you haven't yet gotten VCDS just use the Ross-Tech: Home ad at the top of the page
