Need Advice: Anything would help!

[BitAddict]

Hello everyone, im having some problems and need to know if my guess is a good one.
First off, I have a 90 tsi awd talon. the car is close to stock with some suspension work. I am above average on my mechanical know-how, but still learning as i go.
For a few months now my car has been losing its kick. I began noticing it in first and second gear, but now i can really tell all through out every gear. It has not been that bad so i have been waiting for the weather to warm up. Just recently I noticed when I hit full boost the car bogs down and i lose boost. My valve cover has some small cracks in it and i plan on replacing it after i get some opinions(dont think it pretains to my symptoms). I did a compression check today and was expecting to find really low or no compression in one cylinder. To my surprise, my forth cylinder had high compression(172psi) and some oil on the spark plug. The plug wasnt too bad so i figured my leaky valve cover could have been the problem... I also found that some of my cylinders didnt keep consistant pressure. After examining my downpipe i saw some smoke comming from the flexpipe. That is sort of where I am.
My thoughts are A) i have carbon build up. B)I have a bad valve seal or seals(compression didnt bleed leading me to think my rings are still good)
Im wondering if this is a good assessment of my situation and how i should go about fixing the problems if these are it. Should i try to do the "mccc" cleaning technique? Should I check my valves seals one by one with a valvespring compressor or just remove the head and check everything?
Any Ideas would be greatly Appreciated!!!!!!! Thanks!!!!

 

[Defiant]

How many miles, and what were the compression readings? Difference between cylinders is what really matters.

You may just be getting accustomed to the car.

 

[BitAddict]

92,xxx miles. the other cylinders read from around 154- 162. i dont think its me getting accustomed to the car. a couple of months ago i would get random days where i could definitely tell the car seemed "lighter". some other weird things that happen that might have some clues is that during idle i have sort of an uneven idle(not like normal idle surge) sort of like a hiccup i suppose. also my stock boost gauge seems to jump a little during idle as well. If my problem turns out to be a bad seal or two where might i find a valve spring compressor??? Thanks for the reply

 

[jott5555]

do tha basics.my bet bro is you have a boost leak..

go to www.vfaq.com make a leak tester do the test then check plugs and wires is another good place to start..

mabey pull the intake pipe and see if you have any shaft play

there a couple ideas keep us posted

 

[MrPikolo]

I agree with jot. If, infact you arn't just accustomed to your car, it sounds like you have a vacumm leak of some sort.

http://www.vfaq.com/mods/ICtester.html

Try that out and see if you find anything. Even if you don't, it's a good thing to have around in the future.

 

[BitAddict]

I'm pretty sure I dont have a boost leak around the turbo area...less than a month ago i took the turbo/exaust manifold off to fix the turbo. i replaced the exaust gasket and the turbine housing. Im 99% sure everything went back on right. I re-tightened everything after driving for a couple of days too. All of the turbo seals seemed in good shape. The blue smoke comming from the flex pipe leads me to think a valve seal has been hurt do to high pressure in the 4th cylinder. This might lead me too losing boost i think? Im going to double check my hoses and other possible areas for leaks. If i can find my stock plug wires I will try that too. I picked up some injector cleaner and sea foam for cleaning purposes. Ill see how that goes as well. Im planning on tring to remove the carbon build up first. See how that runs, then check compression again. Thanks for the reply, Ill keep an update!

 

[jott5555]

i kinda think you are overthinking this problem. do like the vfaq says and do the leak tester. if you have any questions about it hit me up on yahoo or aim both screen names are jott5555


good luck bro

jon

 

[crankbender]

Originally posted by jott5555
i kinda think you are overthinking this problem. do like the vfaq says and do the leak tester. if you have any questions about it hit me up on yahoo or aim both screen names are jott5555


good luck bro

jon

Leaky valve seals don't effect boost. A loose exhaust mani will tho....


When you said you had oil on the plug are you sure it was oil and not fuel?

 

[BitAddict]

Ok, i bought some sea foam and stp injector cleaner yesturday. I used the cleaner in a full tank just to at least get rid of some of the carbon build up for another compression check today. I drove about a quarter of a tank on the highway and started blowing smoke out the tailpipe(hard to tell but looks white, has an oil smell to it as far as i could tell) when i got home i did another compression test and got:
4-3-2-1
165-165-160-165

I am now leaning towards a boost leak like you said or maybe head gasket??? going to check for oil in the coolant now. going to head to home depot to make the leak tester...

on a side note(not my problem but, ) if your clutch is slipping could that also mimic the effect of a drop in boost?

 

[BitAddict]

UPDATE: Well im in the middle of a leak test and found some interesting things. Thanks for the suggestion guys!! Found some holes in the top of the SMIC's inlet pipe: Sealed them. The upper stock elbow hose was pretty bad at the bottom: ghetto rigged one to fix problem. Tracked a leak to the Turbo's oil return line(where it flexs) i dont think this is normal. Its leaking oil out of that exact same area also. This could possibly be leaking onto my downpipe causing the smoke??! im going to try and fix the problem tonight or tommarrow. Any ideas for an easy fix? heh. Ill keep updating. Thanks again for the info. it seems to be helping so far!!!!!!

 

[BitAddict]

Update: Car still smokes and power is still bad. boosting has improved quite a bit. im thinking im losing coolant somewhere or my timing is off?? not sure if the timing could cause the smoke though? coolant level doesnt seem to get low either but ive read that it only takes a little bit to cause a lot of smoke. going to try checking every small thing i can find. running out of ideas here. damn.

 

[BitAddict]

Update: Found that the intake camsprocket timing mark is off one toothe. This could be my power loss problem. Still cant find the coolant leak. If coolant IS in fact getting into the cylinders this could cause a bad air/fuel ratio, but my egt isnt showing anything abnormal??? im lost. i think i will lay under my car and kick the jack stand out from underneath it.

 

[crankbender]

are you absolutely sure the car is loosing coolant? If yes you may have a leak in the exhaust bowl. This isn't by any means common but it isn't totally uncommon either.

To test for this make sure the coolant is totally full!! then warm the car up. Shut the car down and IMMEDIATELY pull the plugs. Make sure the engine isn't at TDC (if it is just roll it over a bit).

Does any smoke/steam come out of any of your plug holes?

This is really crappy and happens because of the high EGTs the car sees. Also mitsu uses some funky aluminum alloys. The only real fix is a new head or getting that one welded (if you can find somebody who can do it).

What happens is the water leaks down onto the valves while they are closed and then seeps into the cylinder while they open. This usually doesn't effect the car under boost tho....... under idle it can be murder if the leak is bad enough. It will cause the one cylinder to misfire all over the place and cause alot of hiccups.

I highly doubt this is your problem but you might want to be aware of it.

Do you have an intake pressure gauge? if not get one and we can find out if the car is really loosing boost.

 

[BitAddict]

thanks for the reply. I don't believe that is the problem because I took my car for several drives and immediately after ive done several compression tests. ive never noticed any "steam" comming from the spark plug holes. Its still a possibility though... Ive done a leak test and solved most of the problem with the boost. My leak ended up at the turbo return line. Im planning on getting my timing fixed to see if the car will return to normal driving condition. If it does i will then plug the turbos coolant line and see if that solves my problem. This will all be done with in a couple of days so i will keep posting updates. Thanks again for the idea!