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

 

No signs of any type of boost leak? You can usually hear it.

 

how does the car run engine wise (i.e. hesitation, miss,)? also what type of exhaust manifold do you have? have you checked for any cracks or leaking gaskets before the turbo? unlikely but just throwing it out there.

 

no boost leaks at all, pressure holds steady. Stock exhaust manifold; cannot feel or hear any cracks.

 

I would then start checking to see if your WG is working properly, and not stuck slightly open

 

That's what i thought too, but i don't know exactly how to check it. I'm been trying and searching, but haven't really brought anything up!

 

I pulled the wastegate pressure line off. Went for a drive, and boost was still the same (won't start building boost until max throt above 4,500 rmps, 7.5 psi). With the wastegate line off, i should have seen a huge spike in boost (like 30psi if not careful)!! So maybe the wastegate is stuck open, or my turbo has crapped out. How do i test and see if the wastegate is stuck open?

Also, car runs great. WOT, or just cruising, there are no misfires or hesitation.

 

It now def sounds like it..... You may have to take off your 02 housing and inspect the WG...

Could be the actual WG, could be the actuator