Fuel Trims on a stock TSI

[StreetSleeper34]

I just bought a TSI, which is new for me. I have been heavily modding my N/A for a couple of years now, but I wanted to dabble in the darkside for a while. I used my logger to get some base reading and see how it is running. The kid I bought it off of put a K&N on as well as a o2 dump with full 2.5" exhaust, cat removed. I am getting crazy knock, probably from the o2 dump, but my biggest concern is that the fuel trims are very, very rich. My idle seems ok at 103, but my mid and hi are pegged at 81, which is as rich as it gets. This doesn't sound right. I know these run rich from the factory, but I thought we are striving to keep the trim around 100 on all levels. This rich condition may be causing me some other issues as well. I fouled up some plugs with only 2200 miles on them, and for whatever reason I am going through quite a bit of oil, 3 quarts, after only 1500 miles. It doesn't leak anywhere, and there is nothing in the intake. I believe some of the vacuum lines are messed up, so that could be one of the culprits, but I wanted to verify what stock readings are on a logger so I can go from there. Any help or suggestions is much appreciated.

 

[weith1111]

Wow, you need to do a compression test, that's a lot of oil to go missing.

Do you have a log with o2's on it? I'd wager the o2 sensor is on it's way south.

 

[StreetSleeper34]

Suprisingly the o2 fluctuates pretty normally. And there is no code being thrown up about it failing. Unless these have a tendency to fail and still register normally? I would hate to replace it if it still works.

And as far as the oil, it doesn't have blue/white smoke coming out the exhuast at all. Right now it will puff out black smoke when I am full throttle around 5000rpms with 13-14psi of boost. The engine sputters and craps out. But I am sure this is becaue of the fouled plugs, which I am sure is either caused by the rich condition or possibly oil in the combustion chamber. I am going to pull them tomorrow, once it gets above freezing again. Even if this solves that problem, I still need to fix the running rich part. I am sure that all of these problems are related, but finding what is causing it is more difficult than I thought. I just printed off the vacuum line elimination sheet to see if that will help at all. I still have a feeling that some of those are crossed. Could this have an effect on rich/lean situation?

That is why I am wondering what stock trims look like. Are they suppose to be around 100, or is 81 normal for TSI's? I may not be running rich and what my logger is showing is normal, I just want something to compare them to.

 

[weith1111]

Any air leaking out before getting to the combustion chamber is going to make the car run richer.

Dude, 3 quarts in 1500 miles is not a little blowby or a drip drip here a drip drip there. I hope you are exaggerating because that's A LOT of oil to be losing.

The o2 goes from .2-.8 regularly?

You are still sans turbo right?

 

[StreetSleeper34]

Any air leaking out before getting to the combustion chamber is going to make the car run richer.

Dude, 3 quarts in 1500 miles is not a little blowby or a drip drip here a drip drip there. I hope you are exaggerating because that's A LOT of oil to be losing.

The o2 goes from .2-.8 regularly?

You are still sans turbo right?

I still have to do a boost leak check, but the intercooler piping is still all stock, so leaks are unlikely, but still possible I suppose. Unfortunately I am not exaggerating about the oil situation. I am hoping it may be caused by me putting synthetic in. I am not sure what was used in the past. The block has 140,000, everything else has been replaced or rebuilt...head, turbo, etc.. I am going to put standard oil this upcoming change and see if that makes a difference at all.

Oh and excuse me for being a complete newbie when it comes to turbos, but a sans turbo? What's that?

 

[weith1111]

Having stock IC piping means nothing. I bet you your new car you have boost leaks. A few of them. At minimum expect your TB seals to be blown, and boy are they fun to replace!

Sans is French for "without." I was looking at your profile and confused myself into thinking you were NT.

The synthetic could be the problem. I'd suggest going back to regular oil and/or adding some Lucas oil stabilizer. That stuff is like maple syrup, it's not leaking past anything!

Have you done a compression test yet, your rings have probably seen better days.

 

[StreetSleeper34]

Having stock IC piping means nothing. I bet you your new car you have boost leaks. A few of them. At minimum expect your TB seals to be blown, and boy are they fun to replace!

Sans is French for "without." I was looking at your profile and confused myself into thinking you were NT.

The synthetic could be the problem. I'd suggest going back to regular oil and/or adding some Lucas oil stabilizer. That stuff is like maple syrup, it's not leaking past anything!

Have you done a compression test yet, your rings have probably seen better days.

No I haven't, and I am sure you are right.

My original DSM is a built up n/t, this is my new unforunate project. I shouldn't say that, it has potential, just a lot of mistakes to correct from the previous owner. And having to dive head first into knowing how the turbo system works to fix things is not fun. I was hoping to learn as I go, not immediately.

But if anyone has stock trims, I could still use them. Thanks for all the help so far.

 

[weith1111]

Fixing those boost leaks will make your car a LOT happier:

you won't run so rich
you will get full boost, and sooner
your turbo won't be working so hard making psi that's just getting pissed away through leaks

I had a 4-5 psi leak at the top IC outlet, and it made my car almost undriveable at times. The day I finally discovered it, it breathed life into my car!

Make sure you do the leak test at around 20 psi, some leaks won't present themselves until you get around and above 15 pounds, especially leaks that are from couplers seperating and such.

Oh yeah, and something I tell everyone who is doing basic maintenance, check your base timing (5* BTDC) it makes an even bigger difference than having massive boost leaks!

Good luck, it will be worth it, boost = heaven.