Help! Boost only w/ full throttle and above 4,500

suekie · Aug 14, 2009, 10:40 PM

Need some troubleshooting advice. Car won't build boost until approx 4500 rpm with max throttle. Max boost i get right now is about 7.5 psi. Messed with the boost controller to see if that was the issue (wasn't). I even have the car set up right now to just use wastegate pressure w/ no luck.

Did a boost leak test and car was leaking bad. Found a leaking hose off of the intake manifold. Replaced the hose. Accomplished another leak test, and car is rock steady at 25 psi; but car is still doing the same problem described above.

I bought the car and pretty sure it had some mods on it previously, but returned to stock (except it has a downpipe on it now.) I am thinking the turbo has just gone bad, or maybe the flash on the ECU is for mods that were previously on the car, and wasn't flashed back to stock??

Also, how do you really test the turbo wastegate?

Any input is appreciated. THANKS

Eskimoant · Oct 14, 2009, 07:34 PM

I have the same problem!! did you find out what was causing it??
Ants.

CWhiteRun · Oct 28, 2009, 04:22 PM

Quote:

Originally Posted by suekie

Need some troubleshooting advice. Car won't build boost until approx 4500 rpm with max throttle. Max boost i get right now is about 7.5 psi. Messed with the boost controller to see if that was the issue (wasn't). I even have the car set up right now to just use wastegate pressure w/ no luck.

Did a boost leak test and car was leaking bad. Found a leaking hose off of the intake manifold. Replaced the hose. Accomplished another leak test, and car is rock steady at 25 psi; but car is still doing the same problem described above.

I bought the car and pretty sure it had some mods on it previously, but returned to stock (except it has a downpipe on it now.) I am thinking the turbo has just gone bad, or maybe the flash on the ECU is for mods that were previously on the car, and wasn't flashed back to stock??

Also, how do you really test the turbo wastegate?

Any input is appreciated. THANKS

Are you running a vaccum line (intake mani) to the wastegate or a boost reference line (directly off of the turbo)? Cam timing could be off. Could be a bad wastegate diaphram.

MajorGunHo · Nov 12, 2009, 09:08 PM

I'm not great at stuff like this, but how its not boosting would kind of make me think that the ECU is limiting it in some way?