New Head Gaskets or New Engine?
11-27-2014, 06:33 AM
#11
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In the process
Darn 4.2 has a few likely places:
1. Crossover pipe between banks, at back of engine. Have to pull intake manifold to get it off and put in new O-rings. But you should be able to SEE it leaking there with the engine cover off.
2. Pipe from that crossover pipe to the front of the passenger side head. There is an O-ring from the t-out on the crossover to this pipe…the pipe can only be accessed with the intake manifold off. This pipe/O-ring often wears or leaks if someone diddled with the crossover pipe in the back without removing the intake manifold and replacing the O-ring.
3. Oil cooler coolant transfer pipe..it's in the oil cooler assembly on the rhs of the engine…takes about 10-12 hours to remove the first time you do it, took me about 6 hours the second time.
4. Plastic tube from expansion tank to upper radiator hose. If it's 10 years old, just replace it. Because it WILL break when you move the expansion tank out of the way for something.
5. Expansion tank itself…they seem to last 5-7 years and then 2-5 yrs after that…don't ask.
Head gaskets, not so much. Unless you have a clean piston top (look in the spark plug hole with a borescope) or steam coming out the tailpipe (big steam!) and are in danger of a hydrolock, chances are head gasket isn't blown.
There are also testers that can sense ($50 or so, good for 20-30 tests, more you buy more test fluid) exhaust gases in the coolant that are indicative of a head gasket leak.
1. Crossover pipe between banks, at back of engine. Have to pull intake manifold to get it off and put in new O-rings. But you should be able to SEE it leaking there with the engine cover off.
2. Pipe from that crossover pipe to the front of the passenger side head. There is an O-ring from the t-out on the crossover to this pipe…the pipe can only be accessed with the intake manifold off. This pipe/O-ring often wears or leaks if someone diddled with the crossover pipe in the back without removing the intake manifold and replacing the O-ring.
3. Oil cooler coolant transfer pipe..it's in the oil cooler assembly on the rhs of the engine…takes about 10-12 hours to remove the first time you do it, took me about 6 hours the second time.
4. Plastic tube from expansion tank to upper radiator hose. If it's 10 years old, just replace it. Because it WILL break when you move the expansion tank out of the way for something.
5. Expansion tank itself…they seem to last 5-7 years and then 2-5 yrs after that…don't ask.
Head gaskets, not so much. Unless you have a clean piston top (look in the spark plug hole with a borescope) or steam coming out the tailpipe (big steam!) and are in danger of a hydrolock, chances are head gasket isn't blown.
There are also testers that can sense ($50 or so, good for 20-30 tests, more you buy more test fluid) exhaust gases in the coolant that are indicative of a head gasket leak.
11-27-2014, 10:23 AM
#12
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I replaced PCV valve aka crankcase valve vent, valve cover gaskets and seals, expansion tank, oil pressure sensor, and its still leaking coolant. To the best of my knowledge the oil leak has stopped but the coolant leak is still prevalent. Im in the process of ordering the O rings and the water pipe aka oil coolant transfer pipe. Hopefully that's the problem seeing how that's most common with this year and model. If this isn't the problem, at least its a much needed replacement and then I will move towards replacing the crossover pipes. Thanks for the assistance
Currently I'm using paper towels once a week to skim off the bit of bars-leak floating on the top of the expansion tank liquid…very little left. Apparently the bars-leak has stopped the leak at the crossover pipe/head and the rest is circulating…most of it is out and the coolant is pink.
I'm not saying you should use bars-leak (general consensus is to not!) but on an older car where I'm already not willing to do another TB job (did it awhile ago, good for 60K more) the bars-leak has proven to be a good solution. If it leaks, I'll simply trade the car in.
12-14-2014, 10:41 AM
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Coolant/ Oil leak/ transmission pan leak
Ok guys here is an update: had a coolant leak check done and they said it was the heater hoses so replaced both. I even bought the water pipe aka coolant transfer tube and o-rings but they assured me I didn't need it. That helped a lot with reducing the amount of power I was losing but it did not fix the problem completely. The shop then told me it could be either engine oil seals or the purge valve aka check valve. Along with this lessened amount of smoke continuing to come out I was also informed that I have a transmission fluid leak in my pan. It appears to be cracked or warped.
12-14-2014, 10:49 AM
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Symptoms
In situations where I'm getting onto the freeway or trying to give my v8 engine too much acceleration at one time (which really is the whole point) there is sometimes a significant loss of engine power and in my rear view is a huge cloud of smoke along with slight sputtering but then quickly catches itself and regains most power and control. However when I accelerate at a steady increase as opposed to pedal to the metal, I don't have much of a problem at all. I hope my transmission isn't going out again it only has 144xxx miles on it and I am the 3rd owner. Please help
12-27-2016, 05:40 AM
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Sorry to revive a dead thread, but I'm curious if anyone know what this could be? Sounds like the guy tried everything besides rings - which is a pretty intensive repair. I'm having the same issue with random puffs of smoke, but am suspect of coolant in the expansion chamber as well.
Like the OP, I too had one instance of going WOT and saw reduced power and a very large amount of white smoke out the back. Ever since then, if I run the car hard and shut it down even somewhat hot, upon startup there is almost an identical puff of white smoke. I've replaced most things that the OP has, but have not used a new SMOG pump - that's the next shot because it whines like a siren; however, I do not believe this is the problem because I too have a lOSS of coolant with no visible leak. Or perhaps I'm being paranoid and the expansion tank just fluctuates with engine temp..
Any thoughts/ advice would be appreciated!
Like the OP, I too had one instance of going WOT and saw reduced power and a very large amount of white smoke out the back. Ever since then, if I run the car hard and shut it down even somewhat hot, upon startup there is almost an identical puff of white smoke. I've replaced most things that the OP has, but have not used a new SMOG pump - that's the next shot because it whines like a siren; however, I do not believe this is the problem because I too have a lOSS of coolant with no visible leak. Or perhaps I'm being paranoid and the expansion tank just fluctuates with engine temp..
Any thoughts/ advice would be appreciated!
12-27-2016, 07:24 AM
#16
Sorry to revive a dead thread, but I'm curious if anyone know what this could be? Sounds like the guy tried everything besides rings - which is a pretty intensive repair. I'm having the same issue with random puffs of smoke, but am suspect of coolant in the expansion chamber as well.
Like the OP, I too had one instance of going WOT and saw reduced power and a very large amount of white smoke out the back. Ever since then, if I run the car hard and shut it down even somewhat hot, upon startup there is almost an identical puff of white smoke. I've replaced most things that the OP has, but have not used a new SMOG pump - that's the next shot because it whines like a siren; however, I do not believe this is the problem because I too have a lOSS of coolant with no visible leak. Or perhaps I'm being paranoid and the expansion tank just fluctuates with engine temp..
Any thoughts/ advice would be appreciated!
Like the OP, I too had one instance of going WOT and saw reduced power and a very large amount of white smoke out the back. Ever since then, if I run the car hard and shut it down even somewhat hot, upon startup there is almost an identical puff of white smoke. I've replaced most things that the OP has, but have not used a new SMOG pump - that's the next shot because it whines like a siren; however, I do not believe this is the problem because I too have a lOSS of coolant with no visible leak. Or perhaps I'm being paranoid and the expansion tank just fluctuates with engine temp..
Any thoughts/ advice would be appreciated!
If it's leaking into oil, you can look for yellowish slime and also test the oil for coolant. Time for headgasket.
You might try adding a sealer to your coolant. Don't get the black goop, which will make a mess of your expansion tank, but the bars leak aluminum stuff. I'd say <25% chance of success.
12-09-2021, 04:16 AM
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2000 Audi S6 4.2 v8 steamship
Can the head gaskets be done without removal of the engine? I'm thinking about tackling this myself as I suspected my 4.2 is blown, (always steam coming from the exhaust and occasional gusts of blue smoke 😭
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