so i recently experienced a problem with my car. while driving i am normally boosting 16-18lbs. the other day coming back from school i tried passing someone so i downshifted to 4th and punched it. my car didnt go anywhere and i looked at my boost guage and it read about 7lbs. i then shifted back to 6th gear and my boost went up to about 10lbs and started dropping again to around 7lbs.

when i got home i reloaded the map and everything was working fine. about a day later then same thing happened. and again and again and again...

i spoke with jan about this problem and he thinks its my wastegate...anyone else have any suggestions before i take my car to the dealership and have them look at it?

 

There is a thread somewhere here about upgrading the internal parts of your stock diverter valve with one from the high output audi A3 engine (265hp) you remove the valve and switch the internals. I used to have issues back when I had the unichip and I did this and it helped?? just a thought.

 

There are no CELs?

I think Jan may be on to something. It seems to be dumping boost instead of using it.

 

I have a similar issue in 1st gear, it seems to dump boost but as soon as it hits second it rockets....

 

there are no cels...he said something about internal limp mode

 

i used to have this problem too. i think there is a boost limiter in 1st...not sure, thumper had said something about never rasing(lol) from a dig, just a roll cause there is no boost what so ever in 1st.

 

boost leaks?

 

i checked majority of my tubes...i didnt find any leaks..



oh btw i forgot to mention sometimes when i start my car in the morning, there is absolutely no boost at all

 

You have to let these cars warm up before they start running right.

 

That is definitely true. You won't get full boost till the coolant is around 200 deg. F.

 

Yea there is a limiter...it dumps boost in 1st gear and generally wont boost above 10psi in first. As chakraj said, once you shift into 2nd it flies. You can hear the difference in exhaust tone between the two as well.

If all your boost connections are fine and no leaks...then it might very well be a faulty wastegate. It sense it will hard to get your dealer to warranty it, unless they are cool. Try flashing it back to stock and see if it has any issues. My wastegate stuck close once for some reason, saw almost 30psi . But my dealer checked the actuation, and it was all fine. Never had a problem since.

At the very least, see if you can get them to pull your DME codes, there might be something in there that tells more of the story. The car can be in limp mode without a CEL showing...it makes zero to very little boost in limp mode.


Off topic...but something interesting related to coolant temps has been happening since I Seafoamed my car this weekend. I have Seafoamed without issue before, and as I've always said I'm a big fan of it. This time though, car went into limp mode...from what I'm attributing to misfiring due to the loosened carbon deposits. Did two more treatments and runs beautifully now and limp mode light reset itself.

However, since doing the treatment, my coolant temps will not go above 180ish. Even after driving the crap out of my car, they hover between 177-183. My car always has run ~220 deg...so not sure what's going on with that. Boost also won't go above 15psi, whereas I was running ~18psi before. Car is running great though, and feels much stronger and smoother than it did before the Seafoam.

 

cool, thanks for the info. i was meaning to take it to the dealership but just haven't had time. i think im just going to leave it where im boosting low then have them check it out