ever changing boost

[foety_foe]

i own a tt, 1.8t. iam confused of what the fuck is wrong with the car, had brian at eurotech change all faulty vaccum hoses, re-programed the ecu from APR to GIAC, i changed the diverter valve to a stratmoshpere valve with a strong spring, i also changed the waste gate spring. but anyways after all that my car still does the crazy shit its been doing for a while now. under normal driving situations the car drives fine.

but as soon as i get on the gas here is a list of the following that either happens:
-car starts building boost and as soon as i get to around 5000 rpms it dumps boost from about 18psi to 4ish psi
-car wont build boost, stays at around 6psi through out the rpm's
-car keeps boost until i change gears and then it just wont build boost anymore
-sometimes car runs good keeps boost at around 18psi spike'ing past 20


anybody have any clue because iam oblivious to what the is wrong with the car. i allready spent a lot of money on it trying to get it fixed. i cant keep spending money on stuff and it end up not doing anything. of course i have no warranty and iam not going to the car dealership for them to fix it and charge me an arm and a leg


car is a 01 tt, 1.8t 225 quattro, if that matters

[koukis14]

Its an Audi. Take it to a dealer. It could be your ECM, your blow off valve on a turbo system designed without one, bad turbo, it could be any nmber of things. Audis are a pain in the ass, and tuning them is even more of a pain in the ass. I have had some FUCKED up cars come in the dealership that have been to Eurotech. I would put the stock turbo recirc valve back on and take it to a dealer.

[Z U L8R]

two odd things came to mind. i was thinking about....what if the pcv valve or a vacuum check valve isn't restricting properly all the time creating a boost leak, causing the computer to try to compensate, causing your boost to fluctuate, since your boost is computer controlled. the other, and less likely, was an idea about oil not always getting to your turbo, since the 1.8's have oiling issues, and are known for sludge problems. neither of those are probably your problem, i was just thinking out loud.

sludge motors >_<. if i were in your shoes at this time I would try bypassing the stock boost controller, which takes the computer controlled bullshit out of the loop, and just running a vacuum line straight from a boost source to the wastegate/actuator, then you can at least narrow down the problem to a mechanical or electrical malfunction. ^_^

diagnostics are fun, and costly, you've already tried the process of elimination.... so now try the process of logical deduction.

and change your oil religiously .

[green91]

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