boost problem 5-0-0
 

Need to find out why there is no boost. Just got the car and got 5-0-0 boost. Any ideas?

You have a loose vacuum hose somewhere...I'd put money on it. Check everything thoroughly.

Had the same pattern and found a 3" split in one of the hoses coming out of the intercooler.

Well if your first turbo is only getting 5psi then 10 to 1 there is a leak somewhere from your Y-pipe to the engine. Check the coupling comming right out of the Y-pipe. It will be hard to see unless you remove most of the rubber intake hoses. I found a 2" gash in mine, replaced it and now im boosting strong (on the first turbo). As far as your second turbo... that could be tons of problems... my curve has be 11-0-0... no luck finding my problem. Let me know if you do though.

Chris

PS: heres a link that might help you
http://home.istar.ca/~dvandit/TurboT...shooting.shtml

[QUOTE]Originally posted by 7-sins
[B]my curve has be 11-0-0... no luck finding my problem. Let me know if you do though.

Chris
I know we've gone round and round with your boost problems, but where are you at in your test results?

11-0-0 is a really not good to live with. Let's get this thing nailed and on to bigger boost.

Post your test results. Here is what I would check for and expected results:

1. Test TCA with the solenoids. TCA moves arm w/both vacuum and pressure.

2. Test vacuum chamber, and pressure chamber for pressure hold.

3. actually I could go on and on, but why don't you just post what you have done and the results you got.

Later

Results... hmm let see here.

I have tested both the two solenoids (Turbo pre-control & Wastegate) by that top vacuum tank. Both worked fine.

Tested the one check valve around that area... i think green with a black end. That one was fine.

I have pulled off a hose from the top vacuum tank and it releases air.

I have pulled out all the rubber intake hoses + airbox to check hoses around the turbos, everything looks fine. I did replace one hose around the 2nd turbo side because it was split but that didn't affect anything.

I sprayed carb. cleaner all under the upper intake manifold plus around any other vacuum line cluster, the idle didn't pulse.

Tested both the Turbo pre-control & Wastegate actuators and they moved, worked fine with pressure pump. When static reving the car past 4k I had a friend watch underneath to see if they moved and no, he said the TCA moved. Not sure if the Turbo pre-control and Wastegate would move though.

When driving I have tried letting off the gas (after 11psi) till full vacuum builds then giving WOT, still nothing.

---

I believe that the 2nd turbo isn't spooling then when the gate opens at 4500 to let the 2nds pressure in, it just gives the pressure from the 1st a route to escape back into the atmosphere. I'm also pretty sure that I might be able to find a broken hose, solenoid, or check valve by taking off the intake manifold. I have wanted to but been busy lately.

That's about all I can think of now... It's late and things are fuzzy.

Chris

My boost pattern after doing the hose job is 0-0-0-. wtf what could it be? under load she hesitates and sometimes backfires.