Audi 2.0T Rear Main Seal Hack / Patch DIY

[@project_to_my_son]

This is very useful my 2.0 TSI, turbo on my VW has the same problem, throws lean codes, and sometimes random misfires. The on-and-off EPC and limp modes are the worst. but no other leak than a small rear main seal leak. It's got a plastic intake manifold, and the intake produces an intensive vacuum. I tried closing the intake end while opening the crankcase end of the PCV (like in the video) and read the STFT readings which went down for the first time. Thanks so much for the hack. But before I shut it, till I work on the rear seal, I would love to hear from you since you are an experienced mechanic, 1. Is it ok for PCV to open to the atmosphere and does it make pressure build up in the crankcase? or is it a must to have a vacuum maintained at the crankcase end in the long run? Also 2. Is it ok for the intake manifold to maintain a complete vacuum, will it affect the engine cycles. 3. Is the connection of the crank case to intake solely an emission reduction apparatus? Truly appreciate your response. Thanks again.

[@geeess958]

I'd like to know as well. I tried this before on an 09 A4, same engine (with exception of flex fuel) and it stopped the rough idle but cause oil pressure issues.

[@project_to_my_son]

I tried the hack the engine ran actually really smooth for few minutes and shut by it self. The pCV was emptying to atmosphere and the intake end was sealed air tight. Following that I couldnt start the engine , then I fixed the hose back and the engine gave a EPac and and an extreme rough idle ,where I had to discuss the TPS for a while and re connect to sort it. I think the extreme vacuum in the intake manifold made the throttle plate get stuck in the closed position and thimus caused the EPC and and shut. I run currently in the default mode and I am planning to do a smoke test this week. A rear seal would take at least 900$ and in my 09 CC I'm still thinking wether iwill tleast return it.

[@ALAH31983]

My man! Thank you!!! I'm leaking oil somewhere I don't think it's the rear main seal I think it's coming from the timing cover case. I have a 2011 Audi A4 with the same engine, and what would happen is when the car was very cold it would run and misfire and feel like it's want to stall out but the minute the car was warmed up it would run great I did your method I blocked the tube and I have had zero issues and no flashing check engine light.

[@blakelarsen636]

At 00:52 what is the cable you touched that is resting on top of the engine that rests near the t30 bolt for the ignition rail. ???

[@speedlinegarage]

@@blakelarsen636 outlet for PCV?

[@luiscamacho06]

I just did this to my Q5. How many miles did you put into it before removing engine? Hopefully no downside to this besides a little oil residue or smell

[@elliottjones7508]

Did a variation of this on the '08 I gave to my kid to get it past inspection for lean mix codes. Thank you very much Sir.

[@speedlinegarage]

Happy to hear!

[@project_to_my_son]

Hey buddy tried the same in my VW cc but engine shut after running a few mins, it will truly help if you could briefly explain what you did. Truly appreciate your support.

[@wooggoatmark]

Is that the pcv where the valve is basically a regulator, meaning it can only draw in so much air regardless of where it pulls it from. So opening up a leak at the rear main shouldn't have any effect on how much air the pcv can draw since it's regulated by a valve and not the amount of available air. Just asking. But if there isn't a "valve" then disregard my question because it's no longer valid.

[@mercedesleacock9696]

What else can I use to seal the hose?

[@EJR20]

Oil doesn’t leak through rear main seal??

[@richrottier]

I don’t know, just asking, why not cap off the hose at the top instead of below?

[@DaddyCrane]

White Smoke From Exhaust. Was Bluish/White ETC Until Replaced HPFP etC

[@chrismaddox88]

I’m going to try this now on my s3 having issues will I get a lot of fumes doing this leaving Pcv open and blocking intake off also I don’t know if my Pcv is broken

[@speedlinegarage]

@@chrismaddox88 no fumes at all

[@m1l4nchee]

how much oil are you losing with bad seal? do you need to top up frequently?

[@speedlinegarage]

Well my pistons burn about quart every 400 miles and with rear main seal leaking its down to about 300-350 miles per quart. I’m planning on pulling engine to replace rear main and then doing piston soak for 24hrs then see how many miles i’ll get after. This will be a video for YT soon. Once we get little time at the shop i’ll start my engine pull.

[@m1l4nchee]

@@speedlinegarage My 2009 A4 with 195K is in the same situation, a quart every 350-400. only difference is, to get rid of the lean codes i blocked the codes via software delete instead of your hardware solution. So my rpm fluctuates at idle now. Looking forward to watching your video, even thou i will not be fixing my car. I will let the chain tensioner be the end of it :D

[@coreyklibert1079]

Did anyone else eventually get a P0299 low turbo under boost when doing this? Engine misfire codes went away immediately but got a P0299 after a few drive cycles

[@masonthuanhuynh1914]

Yes, I do

[@mustlovecats442]

P0299 is usually caused by a bad DV. I had the same thing happen.

[@Phytopathology]

Did you need to replace the timing chain kit at all?

[@speedlinegarage]

@@Phytopathology not yet. It’s on its 3rd chain kit right now. Got few more years before i’d need to do it

[@therealpimpskillet]

I tried this, and while it seemed helpful, I wonder if now it's just keeping a bit of pressure in the engine, where the leak I had that was seeping air, is now seeping oil the other direction to the pressure difference. Does this sound like a plausible thing I wonder? I bought the car after someone fixed a motor that skipped time, so there could be a lot of reasons for codes, and a lot of places that could leak, either oil or vacuum related. But after bypassing the PCV like that, I don't get any more 'lean' codes, and the motor seems a lot more stable and less laggy at lower RPMS, BUT now I'm leaking an awful lot of oil where I wasn't before. I can't find an external leak at all testing with ether, so my only other thought was maybe the rear main. What I need is a smoke machine. :(

[@speedlinegarage]

Yes you would leak oil where it originally had failed gasket but you will not throw lean codes and will help you to pass inspection. I went and resealed my entire engine recently and so far 780 miles since oil change and only dropped 1 small bar on my gauge so looks like my engine burns very minimal oil. 1qt per 3500 miles which is well within spec :)

[@speedlinegarage]

Yes smoke machine will help you a lot with locating that oil leak or seeing if your RMS is leaking

[@harveys.2821]

So plugin it does the job, does run boosting with no issues?

[@speedlinegarage]

Nope no issues been running is like this since I posted video. Rear main seal is going to get replaced next week so I’ll plug it back in again.

[@harveys.2821]

That’s a very good diagnostic, I dealing with p0300, p0301 Leaks check compression tested 160psi Pcv replaced only thing I might think I’ll be is carbon buildup 150,000mls or fuel going nuts here with my every day commuter

[@ivancenteno9425]

What causes mail seal to go bad? And how often?

[@speedlinegarage]

Age / PCV failure / Improper PCV use

[@ivancenteno9425]

@@speedlinegarage sounds like a shitty car

[@speedlinegarage]

@@ivancenteno9425 not really. I have 248k on mine. People don’t take care of their cars these days so parts fail and repair is expensive. If people serviced their cars before they break things would be cheaper

[@ivancenteno9425]

@@speedlinegarage yea but now you gotta take out transmission over silly seal in order to drive it how its suppose to

[@evervillalobos9446]

@@ivancenteno9425you sound bitter.

[@shottaspot4147]

Did you every get it fix or you kept it like that

[@speedlinegarage]

Kept it like this for now. Car drives great with no CEL. Rear main still leaking oil but not vacuum

[@Tinfed]

Thanks for posting. What will you do about the rear main seal?

[@speedlinegarage]

@@Tinfed eventually replace it so it does not leak but meanwhile I bypassed vacuum system to prevent check engine codes

[@rezin_3683]

No way I lost the game like this

[@speedlinegarage]

Sorry 😂

[@rezin_3683]

@@speedlinegaragehey, by the way I tried this and my var started running way better, did you have any side effects, did you ever get it fixed?

[@speedlinegarage]

@@rezin_3683 i ran it like that all winter and then pulled engine and replaced RMS and other seals / gaskets while in there. Engine runs great and burns no oil

[@rezin_3683]

@@speedlinegarage I did my rear main and it's still leaking, what other seals and gaskets did you go after?

[@kungfuhustle6363]

By the way you lost the game 😏

[@speedlinegarage]

???🤔

[@DomDeDom]

2:11 😀