View Full Version : Boost Problems and Exhaust Puff.... oil?

11-25-2006, 06:03 PM
Ok guys, car was running great, today I changed the oil again and the filter. Ok so I had to drive across the state again back to school, and I noticed once the motor was warm that my boost was almost all lost, it usually peaks at 12 psi, however it wouldnt let it go past 5 psi at all... however on and off for a while it would then shoot back up to 10-12 psi, but at times it would bog down and not let it back up past 5 psi again.... and then when it eventually did let it go back up to 10 psi form 5, I then also was noticing puffs of exhaust shooting out the back in a grey color.... then after about another 30 minutes, I pulled over, turned the car off and then back on, then the psi was all there again like nothing was wrong, but then about an hour later, it wouldnt let it peak past 5 psi.... its currently running at 10-12 again, however thats cause its just city driving again and turning the car on and off.... what is the deal?

I dont know if this matters but it was a little bit colder on the drive home.... 30 degrees outside, and also I used 5w30 oil when I changed it.... what is wrong with my car? The mileage is roughly around 65,000 Its too dark to go take a look right now, but someones gotta know whats happening. Thanks in advance.


11-25-2006, 06:25 PM
turbo lady may be singing her song... did you notice anything you could compare to throttle cut?

11-25-2006, 06:32 PM
No, not really, however major loss of power when cut down to 5 psi. Nothing that wouldnt be normal though when losing 8 psi. Would this have anything to do with maybe brand of oil or anything? I had just changed it...

11-25-2006, 07:25 PM
spark plugs?

11-25-2006, 07:46 PM
would the spark plugs make clouds of grey smoke.... the smoke would only puff out if i reved the motor and put it into gear, then it would puff out a cloud of smoke... color grey.

11-25-2006, 07:49 PM
Filled with too much oil? If it hasn't done this before, and just started after the oil change, I would look at that as a potential source of the problem...either overfilled, or it's really having a bad reaction to the 5w30 that you put in there...

Maybe run some logs to see what kind of oil pressure you've got?

11-25-2006, 08:14 PM
The oil I put in there was Castrol GTX 5w30 with Anti-Sludge technology protection....

I got the car parked a couple blocks away... and its too damn cold to walk out there right now to check, so say it is overfilled, how bad is that? Ive never overfilled before, but if it is, how could that be making the boost go from 12psi to a max of 5 psi?

11-25-2006, 09:40 PM
too much oil to the turbo @ high psi, good by seals, and yes, if your plugs are bad and your misfiring alot, youll get "pffffff" sound out of your exhaust when you shift and there will be a big cloud of smoke

11-25-2006, 09:40 PM
ya i dont think your oil has anything to do with that.... it does kind of sound like ur turbo is taking a crap, but is unlikely at 65k....what u said right? i would go over and check you vacuum lines. check your wastegate... that might be malfunctioning... just some ideas

11-26-2006, 05:21 AM
Originally posted by maxspeed
too much oil to the turbo @ high psi, good by seals, and yes, if your plugs are bad and your misfiring alot, youll get "pffffff" sound out of your exhaust when you shift and there will be a big cloud of smoke

However, wouldn't gray/blue smoke be an indicator of oil burning? Bad plugs would cause black smoke most likely, where the fuel/air mixture isn't fully burned...

11-26-2006, 06:53 AM
Yeah the car only has 65k miles on it.... I dont see how the turbo could already be going out....

Smootie, what do you mean by check the wastegate? What should I be looking for when I look at it?

11-26-2006, 08:06 AM
Have you check with a vag to see if you have any DTC codes?

Was the smoke a dark grey or a lighter grey?

11-26-2006, 12:28 PM
The smoke was a lighter grey.

I havent checked with VAG yet cause I got a new laptop, its a MacBook and I cant seem to get the vag-com software downloaded, and then I also had issues with using the USB adapter cable....

11-26-2006, 03:06 PM
Ok, so I got another look at it today when walking into work, I noticed that its just letting out a blue-ish grey smoke out of the exhaust t idle. It never did this before the oil change.... any new thoughts? Havent experienced boost loss again, so its still at 12 psi

11-26-2006, 05:46 PM
So ill check for boost leaks and vaccum leaks and ill also try to get vag-com from ross-tech downloaded to my new laptop tomorrow before work.... is there anything else I should check? Im about to just change the oil again with a different kind.... since there seemed to be no issues brfore I changed it. Maybe is too full, I could just drain a little bit and see if the problem goes away. The level on the dipstick is at the same as its always been. My dipstick doesnt have a marker level, where do you guys usually run yours at? mines slightly above the second indent on the stick... but thats where it was at before I changed it this time and the previous time and so forth, ever since I bought it.

SIDE NOTE: Could the N75 valve be going bad? Since the boost was havnig issues? It was acting like a light switch... on and off...

11-26-2006, 06:37 PM
I haven't looked at my dipstick in a while to see what how Audi has it, but on most dipsticks, your oil level should be between the two hashmarks or indents, the bottom is low, the upper one is high...

11-26-2006, 07:09 PM
Ok, so I checked... its a little high. So tomorrow ill slightly drain some.... hopefully this should fix the problems....

Well, mines above the second indent, theres no lines engraved in the dipstick, or anything that says, low or high... So I guess my car has been running high ever since the previous owner... thats annoying and he used to get his changed at the dealership....