camaroguy72

I posted here on the corvetteforum, but it looks like this forum gets more activity.. so here it is.

http://www.corvetteforum.com/forums/...ing-boost.html

Basically, I took my car to a shop while I was out of town to check out an oil leak (time wasn't on my side). They replaced the filler neck, but it was still leaking. I did the valve covers after driving it home and then went for a drive.. could barely get 1 to 2 lbs of boost driving it hard.

I have the UPP twin turbo kit with an eboost 2 controller. External wastegates. Here are the symptoms.

1) Checked all piping, all couplers are tight and no holes in any of the pipes. Intercooler is undamaged, etc.

2) At idle, the intercooler mounted blowoff valves are GUSHING air

3) I hooked up a bicycle tire pump to the wastegates.. the passenger side would actuate the valve with minimal pressure (no gauge on the pump to tell). The driver side I could not get to actuate with the bicycle pump.. there should be between a 5 and 7 lb spring in there at MOST.

4) While parked in neutral, revving the engine I get exhaust out of the wastegate pipe on the passenger side, nothing on the driver side

5) The turbos are much louder, appear to be running faster than before.

6) The car drives like an NA car right now.. when I look at the boost gauge it will go from say -17 to 0psi and sit at 0 unless I get on the highway.. it may peak just under 2 psi and then work its way back down.

My initial thought is the wastegates need to be rebuilt or replaced... anyone else have feedback as to what the issue could be or what to check next? I tried to call UPP but they are closed Monday... and I am trying to get this resolved as it is eating away at me.

SenorThumpy

check your vac lines & routing? first thing i would check just rule out the simple stuff. good luck.

camaroguy72

Checked the vacuum lines and routing, all is well. The car was running fine, setup the same way.. just stopped working properly.

The shop I dropped it off at did say they let the car idle for almost an hour to see if it would leak oil again.. I wonder if that damaged the wastegates.

SenorThumpy

damn, was hoping it would be something stupid simple like that i can't see how idling for any amount of time could damage a waste gate.
Unless the BOVs were closed on idle before (for some reason), them being open gushing air on idle makes sense and isn't a problem unless you have them after a MAF... which obviously isn't the case since you have them on your IC.
If you couldn't get the WG to open manually, that rules out the boost controller(&solenoid) and it sounds like the WG piston is stuck open ... a bit of a suspicious coincidence that a WG just failed while at a shop but I suppose stranger things have happened. pop it open, see if the spring is broken or the diaphragm is damaged...etc. That would match all of your other symptoms.

camaroguy72

Sounds good. CK from UPP also replied and suggested the same.. so I feel I'm on the right track. Just needed confirmation since I'm fairly new to the Turbo thing. I learned more this weekend than I did my whole life up until now.

jrpimp00

iTrader: (17)

Post pics of your engine bay. May notice something wrong that way.

camaroguy72

If you click the corvette forum link the pics are there... but I'll post some here when I get home. Car was running just fine the way it was, although ck indicated my closed catch can and no check valve could he causing high crankcase pressure.. although no boost right now the way it's running.

The wastegate on the passenger side was making odd noises today driving home from work , I'm anxious to pull it apart.