2001 Audi A4 1.8T White smoke after long idle

[dtmdreaming]

I purchased my Audi about 6 months ago. I drove it about 3 hours back from where I purchased it. I never saw any smoke whatsoever. I parked it for a few days, and went to crank it, then I noticed after it had been idling for about 8 minutes alot of white smoke was coming out of the exhaust. The smoke went away after a few minutes. It only does this at idle. Sometimes if I dont let it idle for longer than 2 minutes before I take off, I wont see it at all until the next time I let it idle for a while.

I am not loosing any coolant, nor am I overheating. Its a weird smelling white smoke.

I have replaced the coolant temp sensor, spark plugs (twice), half moon seal, cam chain tensioner gasket, valve cover gaskets, cleaned most of the crankcase breather hard lines. I have also changed my air filter, and fuel filter. Both of my O2 sensors are new.
I just don't understand the white smoke? It would be easy if I was loosing coolant or overheating, but I'm not really getting anything to lead me in the right direction.

The car is stage 1 chipped on 93 octane. have only had it chipped for about 2 weeks, driven it maybe 8 hours total.
I have a catback exhaust, forge diverter valve, and a "pod filter".

This was happening even before I got the car chipped. This car is a weekend warrior and not my daily driver.

This weekend I am going to replace my intake manifold gasket, as well as the crankcase breather hoses under the intake manifold, and see if that helps out any.
The car runs really well and very strong, I just don't like the smoke because it is embarrassing. I drive the car hard, but I always keep my oil changed, and fix something everytime a cel pops up. Which has only been an o2 sensor and coolant temp sensor so far.

Any help is appreciated, I love this car this is my 2nd B5, and Iv'e also had a B6 1.8t. I don't want to give up but I am just puzzled.

Also I have searched this forum to make sure this question has not been asked before, and it seems like I may have a unique case here.[IMG][/IMG]

[Davdraco1]

I was having the same thing happen to me then I realized I was getting a check engine light at the exact time it started to smoke. The code was for my primary o2 sensor so I replaced that and problem solved. If you have any codes see what that are and start there.

[SN95Audi87]

How many miles are on your A4? The original turbo on mine went out at 175k. It was spewing white smoke after the turbo seal let go the other day going up a big mountain in my town. If your turbo is not making a dentist drill noise, it will eventually will and cause the turbo to completely fail. It seems like you replaced everything under sun, so I would start paying attention to the turbo. Mine started make light puffs of blue smoke at idle from take off then bam, turbo blew a few days later.


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[SEATLRallyTeam]

Does it only happen when engine is cold and it's warming up on idle? If so, it's just condensed water in your exhaust. Post a video of the smoke if you can

[dtmdreaming]

I am not getting any Check engine lights. All I have to check it with is an OB2 scanner though. Are their more O2 sensors than the ones that are on the cat?

The turbo will be my next replacement I suppose. The car has 180000 miles on it, but luckily I bought it for 1600 dollars.

Also I don't believe its condensation, this is a different type of smoke.

[Wrath And Tears]

White smoke = coolant
Blue smoke = oil

It its truly white smoke then you need to start thinking head gasket or something like that.

[dtmdreaming]

White smoke = coolant
Blue smoke = oil

I'm not loosing any coolant, iv'e been at the same max level since the day I bought it. I have noticed a little oil in the big hose that connects to the throttle body.
Not sure if that has anything to do with it, also oil keeps leaking around my oil filler cap, I ordered a new oil cap to see if that will correct that issue.

How much does the average Euro mechanic shop charge to do a head gasket replacement if it is the head gasket?
I try to avoid taking my vehicles to shops for maintenance, but with my work schedule it would take me a while to get it done, and I might as well get them to replace the timing belt and water pump while its in pieces.

[Wrath And Tears]

If it is white smoke then it can't be anything other then water getting into the exhaust. The smallest amount of coolant will create a large amount of smoke. Have you been checking the coolant level on the exact same surface every time? Also if you haven't seen the difference between white and blue smoke then its probably blue and you can't tell.

Honestly it sounds like you don't drive the car enough. Go actually drive it. Beat the shit out of it, that is what a built B5 is meant for. We call this an Italian tune up. It works wonders. OOOOOOOR, you have an issue and the Italian tune up will make it worse / blow the car up. At least then you know what to fix.

[Davdraco1]

I never thought about water in the exhaust but when it was warming up and started smoking it would thru a code for my primary o2 sensor.

[dtmdreaming]

If it is white smoke then it can't be anything other then water getting into the exhaust. The smallest amount of coolant will create a large amount of smoke. Have you been checking the coolant level on the exact same surface every time? Also if you haven't seen the difference between white and blue smoke then its probably blue and you can't tell.

Honestly it sounds like you don't drive the car enough. Go actually drive it. Beat the shit out of it, that is what a built B5 is meant for. We call this an Italian tune up. It works wonders. OOOOOOOR, you have an issue and the Italian tune up will make it worse / blow the car up. At least then you know what to fix.

Oh it gets checked on the same surface everytime, always at the same level. I drive it hard every time I get in the car. So I don't think that's an issue.

[NickW3]

I'm having the same problem with mine. Mine dumps out tonsss of white smoke if I'm at idle for more than 2-3 minutes and goes completely away when driving. It smells a little weird like you were saying, not like oil and not like coolant. It does it when warm or cold, it doesn't matter. I also am running no cat though with a straight pipe and a FMIC with no tune and it runs like shit of course. I think mine is just running lean when at idle because of having no tune. It sounds like you're having the same kind of smoke as me, even though your car is tuned properly.

maybe your post cat o2 is just bad somehow, (even though it's new) and its throwing your car off and making it run lean. Thats basically what is happening to my car because of having no cat. idk if this helps but it seems similar to mine

[Avant Nate]

imo valve seals

[Davdraco1]

I'm having the same problem with mine. Mine dumps out tonsss of white smoke if I'm at idle for more than 2-3 minutes and goes completely away when driving. It smells a little weird like you were saying, not like oil and not like coolant. It does it when warm or cold, it doesn't matter. I also am running no cat though with a straight pipe and a FMIC with no tune and it runs like shit of course. I think mine is just running lean when at idle because of having no tune. It seems like the white smoke to me is like the smoke you get when an engine runs lean. It sounds like you're having the same kind of smoke as me, even though your car is tuned properly.

maybe your post cat o2 is just bad somehow, (even though it's new) and its throwing your car off and making it run lean. Thats basically what is happening to my car because of having no cat. idk if this helps but it seems similar to mine

Your secondary o2 has nothing to do with afr. That's what your primary is for.

[NickW3]

Your secondary o2 has nothing to do with afr. That's what your primary is for.

You're right i clearly wasn't thinking lol I guess in that case, then I'm having the same problem as the OP.

As far as i know oil will cause white smoke when it vaporizes in the exhaust/turbo. Blueish when burned in the cylinder combined with fuel. Check your oil and see if it's low. Might be a bad turbo

[dtmdreaming]

It will do this even after you drive for an hour or two, if you stop and idle for a while here comes the smoke. You wont see it when the car is in motion.
You can actually rev the engine a little while its smoking and the smoke level will decrease. which is kind of weird.

[Davdraco1]

When mine smokes is just white. No smell to it. I wouldn't be surprised if it was water vapor as the exhaust comes up to temp.

[dtmdreaming]

When mine smokes is just white. No smell to it. I wouldn't be surprised if it was water vapor as the exhaust comes up to temp.

It magically quits when you are actually moving. You could drive from Atlanta to Florida without seeing smoke, but if you stop at a store and let it idle for a bit it will start smoking.
I would honestly feel better If I was loosing coolant and overheating, because I wouldn't have to play the guessing game. It would be a head gasket. My cars issue just doesn't make sense to me.

[Davdraco1]

Idk. I replaced my primary o2 sensor and it fixed the issue.

[dtmdreaming]

Idk. I replaced my primary o2 sensor and it fixed the issue.

So I'm assuming the primary o2 sensor is the first one I see, closest to the turbo?

[NickW3]

So I'm assuming the primary o2 sensor is the first one I see, closest to the turbo?

correct

[Davdraco1]

Yea. A 22mm crows foot or an 02 socket is needed to get it out.

[dtmdreaming]

Yea. A 22mm crows foot or an 02 socket is needed to get it out.

I changed them both when I first got the car, but i didnt know the front o2 sensor was referred to as the "primary". I had an o2 sensor socket that I used but I cannot find it, along with some other tools that somehow dissappeared lol. I will have to order another one.
I hope that neither one of them have gone bad, I got a CEL for o2 sensor about a day after I was running my tune, but I erased it. My secondary o2 sensor is disabled on the tune.

[Davdraco1]

I'm tuned and get a code for my primary o2 and I erase it and it stays off for a few months and the car runs fine. I don't worry about it

[dtmdreaming]

Well, I replaced just about everything on the crankcase breather system that I could get my hands on last night, as well as cleaned my throttle body, and installed a new intake manifold gasket. I let the car idle for about 10 minutes, maybe more. The only smoke I saw was condensation type smoke because I haven't driven this thing since last sunday. Idles ALOT better, runs alot stronger, and my throttle response is alot better. The pcv valve and all of the major components of the pcv system were clogged completely. The PCV valve itself was filled with gunk and the T-hose was clogged up badly as well. It seems to have fixed the smoke issue, so far. I also replaced my oil filler cap, and dipstick tube.

[3 bar]

I second the turbo seal. Probably a good time to replace or rebuild the turbo