Smoke from under hood

[JRYtheS4]

2011 S4. I have smoke emanating from between my coolant tank and the valve cover. I replaced the valve cover gasket today because I saw leakage. After I got done I had a helper rev the car while I looked under the hood for oil. What I noticed was that the smoke goes away whenever the car is revved, and returns at idle.

Would you agree that this is likely an exhaust leak? It seems to be located right where the cat meets the header.

Edit: I saw smoke before I changed the vc gasket. That and the oil leak is what triggered me to change it.

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[poloshirt]

Burning coolant and oil both have a pretty distinctive smell. Does the smoke smell like either? Also, ask yourself, does it make sense that you suddenly have an exhaust leak after replacing the valve cover gasket? I would say no...My guess is something, either oil or coolant, dripped onto the exhaust and is slowly burning off.

[JRYtheS4]

Burning coolant and oil both have a pretty distinctive smell. Does the smoke smell like either? Also, ask yourself, does it make sense that you suddenly have an exhaust leak after replacing the valve cover gasket? I would say no...My guess is something, either oil or coolant, dripped onto the exhaust and is slowly burning off.I didn't make it clear in my post but what I meant was I changed the vc gasket after I saw smoke and an oil leak, but didn't realize that the smoke was disappearing whenever the car is revved.

The smoke doesn't really smell like much of anything. Maybe a little oily but not strong at all.

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[JRYtheS4]

For posterity's sake, figured I'd wrap this one up.. took another look at it Sunday, and realized pretty quickly I was wrong. The smoke is actually the timing cover or filter housing puking oil onto the exhaust. I had been sick so I couldn't really smell it, just smelled and looked like exhaust to me.

So now I'm doing a timing cover reseal, replacing cats if they look worn, replacing upper chain tensioners, motor mounts, and replacing the filter housing. Also redoing my PCV since I used the wrong part 2 years ago, to hopefully reduce it's 1qt/1000mi oil consumption.

Honestly it's impressive how much room is gained by removing the false firewall. Makes it not too bad to get at the back (top) of the motor. Decided not to do a full engine out this time.

Maybe by the end of this I'll get to enjoy my car for a bit before I have to replace the 133,000mi clutch! XD

I'll post here my experience and any updates.

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[Mfryman1]

If you are planning to do the above work, engine in, you are really undertaking a event that is almost impossible with the engine in the bay. I tried it myself and getting to the bolts to remove the cats, so you can remove the heatshield, so you can remove the air valves, so you can remove the timing chain covers is really challenging. It is almost impossible also to get the locking pin into the crank because it is buried behind the drivers engine mount bracket. Even with the engine mount removed, and the oil cooler, and the ac condenser, and the power steering pump pulled out of the way. I'm not sure if any other readers have tried what you are maybe thinking, but after busting my knuckles for days to get the covers off, then trying to remove and install the tensioners, get the sprockets re-installed properly you have the top of the engine torn off. After I made the decision to pull the engine, and a quick trip to harbor freight for a engine hoist and load leveler, I had the engine out in 3 hour by myself. Best decision I made in the project. If you want details and Pictures of issues let me know as I made a document trail of the issues I had.

Maybe I am chiming in without cause and I welcome comments from other who may have done this with success. I am curious!

297026

297027

[JRYtheS4]

If you are planning to do the above work, engine in, you are really undertaking a event that is almost impossible with the engine in the bay. I tried it myself and getting to the bolts to remove the cats, so you can remove the heatshield, so you can remove the air valves, so you can remove the timing chain covers is really challenging. It is almost impossible also to get the locking pin into the crank because it is buried behind the drivers engine mount bracket. Even with the engine mount removed, and the oil cooler, and the ac condenser, and the power steering pump pulled out of the way. I'm not sure if any other readers have tried what you are maybe thinking, but after busting my knuckles for days to get the covers off, then trying to remove and install the tensioners, get the sprockets re-installed properly you have the top of the engine torn off. After I made the decision to pull the engine, and a quick trip to harbor freight for a engine hoist and load leveler, I had the engine out in 3 hour by myself. Best decision I made in the project. If you want details and Pictures of issues let me know as I made a document trail of the issues I had.

Maybe I am chiming in without cause and I welcome comments from other who may have done this with success. I am curious!

297026

297027I appreciate your input for sure. I want to pull the engine but I'm unfortunately stuck working in someone else's garage space this time and they don't want me to pull it. I tried explaining that it would probably take less time and energy. But it is what it is. I'll give it a shot with the motor in. I was crouching on top of my supercharger, standing on my head to look at the cat bolts and soak them in penetrating oil. I might pull off the hood to get more comfortable access. I saw how the sai valves and heat shields are all up in the way. Where I'm at now though I feel like I'm 1/3 of the way to having the motor out. I studied the Audi method for the engine pull and it isn't bad. Maybe I'll wait until it's warm and just pull it in the driveway.

I'm hoping my cats are in good condition so I don't have to undo the drivetrain to remove them. From the looks of it I can unbolt them and move them away just enough to undo the sai.

I found your posts about when you attempted it. If you have any more advice or photos feel free to post them here I'd appreciate it.

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[Mfryman1]

I am sharing a link to my dropbox for the photos I took during the disassembly of the entire top of the engine to access the PVC, thermostat etc. The cam covers must come off to install the cam bridge tool to lock them at TDC to replace the tensioners.

https://www.dropbox.com/scl/fo/zu5aacqm0nddfsun75u3y/h?dl=0&rlkey=d1htom07u4tt19qonqq3ekme4

[JRYtheS4]

I am sharing a link to my dropbox for the photos I took during the disassembly of the entire top of the engine to access the PVC, thermostat etc. The cam covers must come off to install the cam bridge tool to lock them at TDC to replace the tensioners.

https://www.dropbox.com/scl/fo/zu5aacqm0nddfsun75u3y/h?dl=0&rlkey=d1htom07u4tt19qonqq3ekme4Thank you! It's funny, your supercharger bearing change process looked EXACTLY like mine. Did the same exact bearing press setup at work and machined my own bearing press tool. Tough to get the charger stood up on end and get it all lined up.

I've been into the valley of the engine about 5 times and carbon cleaned twice but haven't done anything on the back of the motor yet.297139

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[bakedziti]

I appreciate your input for sure. I want to pull the engine but I'm unfortunately stuck working in someone else's garage space this time and they don't want me to pull it. I tried explaining that it would probably take less time and energy. But it is what it is. I'll give it a shot with the motor in.

FWIW, the tech at my indy shop asked if I cared if the engine came fully out for the timing job or not when I dropped it off and explained that with an engine support bar and the car on a lift, they’ve done 3.2s previously without removing the engine fully and instead by simply lowering it down with a support bar (kind of the opposite of what we typically do for engine mounts by raising the engine). I’m honestly not sure what else would be involved here as I let him know I purchased all the hardware for the manual procedure(s) but if they were more comfortable with another less laborious route then I was open to at least hearing about it.

Granted I spent serious coin with them and have a more personal relationship with my shop than most, but to me it’s nice to have a shop and a tech call me directly and discuss these topics with me openly.

The biggest issue with leaving it from what I can see is the lack of space to see or use the tools to lock the cams.

[JRYtheS4]

FWIW, the tech at my indy shop asked if I cared if the engine came fully out for the timing job or not when I dropped it off and explained that with an engine support bar and the car on a lift, they’ve done 3.2s previously without removing the engine fully and instead by simply lowering it down with a support bar (kind of the opposite of what we typically do for engine mounts by raising the engine). I’m honestly not sure what else would be involved here as I let him know I purchased all the hardware for the manual procedure(s) but if they were more comfortable with another less laborious route then I was open to at least hearing about it.

Granted I spent serious coin with them and have a more personal relationship with my shop than most, but to me it’s nice to have a shop and a tech call me directly and discuss these topics with me openly.

The biggest issue with leaving it from what I can see is the lack of space to see or use the tools to lock the cams.Interesting. Well I'll have to have the engine supported to do the mounts anyway so I'll let you know if that suggestion gives me more room.

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[JRYtheS4]

Finally getting started on my oil leak. Tldr, it's leaking from somewhere in the timing cover area so badly that it smokes after a short drive. So it's been on jackstands waiting for me to get time to work on it.

Did a compression test today, and sent an oil sample off to Blackstone. Based on my compression numbers, I think the bottom end will be staying together this time. July 4th weekend, this engine and trans are coming out.307214

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[SwankPeRFection]

“If” the engine is burning oil and it smokes from the bay while idling after a drive, it’s due to broken/leaking downpipe flex joints. This is what mine was doing. Replaced downpipes when this was happening and no more smoke from the engine bay. Burning oil on these cars (like when you burn a lot) is going to be from valve seals, even though Audi mechanics will tell you it’s either the PCV or rings. 🙄 Every other fucking engine on the planet burns and smokes hella oil out the exhaust under the same conditions and it’s always worn valve seals, but Audi thinks it’s special. Lol

[JRYtheS4]

“If” the engine is burning oil and it smokes from the bay while idling after a drive, it’s due to broken/leaking downpipe flex joints. This is what mine was doing. Replaced downpipes when this was happening and no more smoke from the engine bay. Burning oil on these cars (like when you burn a lot) is going to be from valve seals, even though Audi mechanics will tell you it’s either the PCV or rings. [emoji849] Every other fucking engine on the planet burns and smokes hella oil out the exhaust under the same conditions and it’s always worn valve seals, but Audi thinks it’s special. LolThat could be. In my case, I know it's leaking oil out the timing cover because I can see it happening. I wouldn't be surprised if I also find the oil filter housing leaking at the bottom. It also rattles quite a bit at start up, which is what's driving me to pull the engine and do the timing job and a clutch. I thought about doing the valve stem seals while it was out.

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[SwankPeRFection]

Honestly dude, I would do them. You’re already kind of in there and while it sucks to pull the gears and cams out, it would suck to put it all back together and still have old worn out ones still in there contributing to issues. If you’re wanting to keep driving the car and love it, now’s the time to do those seals. The engine’s coming out anyway.

[JRYtheS4]

Honestly dude, I would do them. You’re already kind of in there and while it sucks to pull the gears and cams out, it would suck to put it all back together and still have old worn out ones still in there contributing to issues. If you’re wanting to keep driving the car and love it, now’s the time to do those seals. The engine’s coming out anyway.Do you have a line on a valve spring compressor tool that will fit a 3.0t?

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[ValidatedS4]

Following along on this.

I’ve torn my engine down currently for PCV, thermostat, water pump, supercharger oil/Intercooler, carbon cleaning, fuel injector cleaning, valve cover, spark plugs/coils, oil filter housing gasket..

Also added the oil pressure check valves from the B8’s to help with my less than 1 sec rattle.

I saw some leaking (probably oil filter housing) and also the driver side upper timing chain covers slightly.

After finding out the cats need to come off for the timing covers I’m going to leave it for next round of maintenance and probably will be engine out as well for timing guides/tensions, motor mounts, clutch.

I’m at 182K and will be using this as a weekend/dedicated track car until the wheels fall off. Saving for the Merc racing super changer :].

I’ve tightening all the timing cover bolts that I could reach since I read them backing out can cause leaking. Some people suggest blue loctite when resealing them.

Didn’t want to add more “while your in there” as I actually want to enjoy the car for the summer.

Good luck with the process JRY.


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[JRYtheS4]

Following along on this.

I’ve torn my engine down currently for PCV, thermostat, water pump, supercharger oil/Intercooler, carbon cleaning, fuel injector cleaning, valve cover, spark plugs/coils, oil filter housing gasket..

Also added the oil pressure check valves from the B8’s to help with my less than 1 sec rattle.

I saw some leaking (probably oil filter housing) and also the driver side upper timing chain covers slightly.

After finding out the cats need to come off for the timing covers I’m going to leave it for next round of maintenance and probably will be engine out as well for timing guides/tensions, motor mounts, clutch.

I’m at 182K and will be using this as a weekend/dedicated track car until the wheels fall off. Saving for the Merc racing super changer :].

I’ve tightening all the timing cover bolts that I could reach since I read them backing out can cause leaking. Some people suggest blue loctite when resealing them.

Didn’t want to add more “while your in there” as I actually want to enjoy the car for the summer.

Good luck with the process JRY.


Sent from my iPhone using Audizine (http://r.tapatalk.com/byo?rid=87676)Thank you. Same boat here, hate adding more "while you're in there" as I too want to drive and enjoy my car this year. Was glad I didn't see any need to do rings, I was pretty anxious about that. My car has visible oil dripping off the x brace, quite a bit. And oil seems to burn off on the cat/header as soon as it warms up. So definitely a big leak I unfortunately can't ignore any longer. Fwiw, it's leaked for more than a year, it's just gotten bad enough to address. I figure the sealant they use on the timing cover must start cracking after all those heat cycles. I can actually watch oil/air bubbles slowly pop up from the timing cover seam on the top edge of the cover on the driver side. It's totally failed.

I'll be posting as many photos as I can and blogging my experience in this thread.

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[ValidatedS4]

Thank you. Same boat here, hate adding more "while you're in there" as I too want to drive and enjoy my car this year. Was glad I didn't see any need to do rings, I was pretty anxious about that. My car has visible oil dripping off the x brace, quite a bit. And oil seems to burn off on the cat/header as soon as it warms up. So definitely a big leak I unfortunately can't ignore any longer. Fwiw, it's leaked for more than a year, it's just gotten bad enough to address. I figure the sealant they use on the timing cover must start cracking after all those heat cycles. I can actually watch oil/air bubbles slowly pop up from the timing cover seam on the top edge of the cover on the driver side. It's totally failed.

I'll be posting as many photos as I can and blogging my experience in this thread.

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Oh damn, yeah mines not bubbling like what you’re describing. I’m glad there’s still owners on this platform who aren’t running for the hills when it comes time to do this level of care/maintenance.

And yes please document what you run into while tackling all of this as I’m sure all the “new to me” owners will appreciate it.


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[JRYtheS4]

Oh damn, yeah mines not bubbling like what you’re describing. I’m glad there’s still owners on this platform who aren’t running for the hills when it comes time to do this level of care/maintenance.

And yes please document what you run into while tackling all of this as I’m sure all the “new to me” owners will appreciate it.


Sent from my iPhone using Audizine (http://r.tapatalk.com/byo?rid=87676)Bottom line for me is, where else am I going to get an AWD 6 speed sedan? With 400hp? And supercharger noises? Short answer is, I'm not. This is the last hoorah for 6 speed dailys. So I'll fix it.

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[JRYtheS4]

Finally got time away from fixing other cars to fix mine..309382

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[SwankPeRFection]

Finally got time away from fixing other cars to fix mine..309382

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Can you do me a favor. If your car is still apart like this, take a pic from above the furthest back area behind the supercharger pointing down towards the secondary O2s? I’ve always wondered if it’s worth taking out the false firewall to get better access to those sensors when trying to do spacers. Passenger side is a bitch to get to no matter what it seems.

[JRYtheS4]

Can you do me a favor. If your car is still apart like this, take a pic from above the furthest back area behind the supercharger pointing down towards the secondary O2s? I’ve always wondered if it’s worth taking out the false firewall to get better access to those sensors when trying to do spacers. Passenger side is a bitch to get to no matter what it seems.Very accessible. Have to remove false firewall and cross brace, might take 30 minutes the first time.309394

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[SwankPeRFection]

Can that false firewall be taken out without messing with the heater core lines and other shit that passes through it? I’m trying to remember from memory last time I looked at it.

[JRYtheS4]

Can that false firewall be taken out without messing with the heater core lines and other shit that passes through it? I’m trying to remember from memory last time I looked at it.Have to take off heater core lines, but they aren't difficult.

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[JRYtheS4]

Where I'm at as of end of Saturday. Started finding all the bell housing bolts, looks like some of the upper ones are tough to get at. Got the flex plate bolts out, have to drop the sway bar and the steering rack to get the motor mounts and she'll be out finally.

Haven't figured out how to remove the ac compressor yet but the bolts looked accessible. Trying to leave the ac together and in the car.309461

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[SwankPeRFection]

Might wanna update your signature because I see an upgraded crank pulley there. 😆

[JRYtheS4]

Might wanna update your signature because I see an upgraded crank pulley there. [emoji38][emoji2958] lol. The 206 and heat exchanger are going in when this goes back together.

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[GAR92677]

Oil filter housing is very common. Start with doing the filter housing gasket and the upper timing covers on the heads they both leak onto the back of the exhaust.

[JRYtheS4]

Oil filter housing is very common. Start with doing the filter housing gasket and the upper timing covers on the heads they both leak onto the back of the exhaust.Have a new oil filter housing for it ready to go in [emoji106] It's getting a full timing chain service so everything will get new sealant. Valve covers were already done. It's tough to keep oil inside the engine sometimes!

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[JRYtheS4]

Well, got some really good advice from someone local to me and decided to leave my chains alone and focus on what was actually broken. I got my timing covers resealed yesterday. Trick was to lower the whole front subframe. I unbolted all 8 subframe bolts and lowered the whole front assembly via the lifting points and the supercharger. Once I did that I had decent access to remove the cats. Still a PITA. Checking the cats, both showing some signs of collapsing substrate so they're not going back in. Putting in my jhm testpipe to catted baffled downpipe w/xpipe. My plan is to try to keep both resonators that are part of my Milltek non-res system, so I'll have to shift some things around to make it all work. Not sure if anyone has tried that before so we'll see if it sounds like trash or not! Sounded great with stock cats.

Now on to the fun stuff, 206mm pulley, ie dual pulley tune, cts turbo heat exchanger, new trans mount, and jhm shifter linkage. 310674310675310676310677

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[SwankPeRFection]

That plastic on the chain tensioner up top is looking a little old and dark. That’s really the big worry with these things, I’d that plastic starts to break down and snap off due to brittleness, etc. It depends on age of car and how many miles are on it, but if you’re pushing over 150k and plan on keeping it still for a while, it’s something to invest the time/parts into to reset the clock sort of speak. Anyone getting close to 200k I would definitely start planning for having to do them.

[fastboatster]

you didn't have to remove the cats completely to reseal the covers, you just needed to unbolt them and move them out of the way. They are not getting in a way whatsoever. covers can be installed from the top, although you'd need to remove the supercharger and oil filter housing. If you unbolted the subframe, you're 80% away from the removing the entire drivetrain. As for the plastic guides, I also think it's a good idea to replace those, but you'll need to retime the engine to do it right. On my first engine with 150kmiles which spun the main bearings they were all brown but still not brittle. One my second engine which was claimed to have 93 kmiles (but probably more like 193), they were not nearly as brown but driver side guide was broken. Anyway, what I'm saying is you got very close to having it out, just go ahead and do the complete timing system, it will be 100% worth it for your engine. As for my engine, when I pulled it out, I quickly realized that replacing upper chain tensioners I did this winter was not worth it for this engine, and the money and effort need to be used to get a GOOD engine. This one had been very deeply disassembled at some point and put together with blobs of rtv hanging out in some oiling channels - worn main, rod bearings and oil control rings worthy of 2.0 tfsi

[JRYtheS4]

Well, my goal was to remove the cats so they had to come out. And like @fastboatster , I decided that this engine is not worth investing in. I'll let you know when it finally dies.

Other issues, a 7pk1320 doesn't come close to fitting a 206mm lower with a stock upper pulley, so I must have been misinformed when I bought this belt. And the milltek non-res does not mate up to the jhm catted baffled downpipe/xpipe, so be prepared to do some fab work. I'm a little sad I'm losing the center Milltek resonator to run the jhm kit, I liked the tone as it was. It isn't possible to fit the entire jhm downpipe and the milltek resonator before it hits the rear cross brace.



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[fastboatster]

Well, my goal was to remove the cats so they had to come out. And like @fastboatster , I decided that this engine is not worth investing in. I'll let you know when it finally dies.

Other issues, a 7pk1320 doesn't come close to fitting a 206mm lower with a stock upper pulley, so I must have been misinformed when I bought this belt. And the milltek non-res does not mate up to the jhm catted baffled downpipe/xpipe, so be prepared to do some fab work. I'm a little sad I'm losing the center Milltek resonator to run the jhm kit, I liked the tone as it was. It isn't possible to fit the entire jhm downpipe and the milltek resonator before it hits the rear cross brace.



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didn't really have to lower the subframe to get the cats out, especially if it's 6MT. Why did you decide not to "invest" time into changing the timing chains etc? I didn't because I saw that all the oil control rings were clogged, main bearings had copper showing through in some spots, I was worried that it had spun the main bearings at some point and was put together to make the car it came from to sort of run. If your engine is still running strong and not burning too much oil, it's worth holding on to. It's kind of a lottery getting these engines, especially if you decide to stick to only b8 s4 engines. I'm going to say take care of yours and then go dual pulley.