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Turbo not Boosting, Throttle is weak

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Old 10-14-06, 08:36 PM
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Question Turbo not Boosting, Throttle is weak

OK guys, need some help here!

I took out the turbo, replaced fuel lines, cleaned injectors, new clips, removed twin-scroll(welded hole and capped line), put in 3in-TID, got a fcd, cleaned all grounds, made new omp lines, new spider vac lines, changed all gaskets(turbo to dp, turbo to exhaust, exahust to LIM, inbetween UIM and LIM, and more), changed out crusty vac lines, and ported the wastegate to 26mm.

Currently I have an FD fuel pump and I also re-wired it

Put everything back together and once the oil pumped through the new lines, the smoke went away. So I jumped in the car to take her for a spin. Sounded alot beefier in a good way.

Well, the turbo did not boost at all. I ported the turbo because I am going 3in free flow exhaust pretty soon, but right now have stock. I disconnected the fcd to see if I was getting any boost, and that I was not. Would porting to 26mm with a stock system other than the fuel pump and TID, cause the car not to boost?

Also, something seems to be lagging with the gas. I cant even pill out, much less get on the highway faster than a beat up truck! Think there might be a vac leak...think that might be the case? I forgot does the line under the UIM, connects UIM to engine and is really small, run as a vac line or coolant or what?

Thanks for anyhelp!

Update tomorrow after I do some work on figuring things out...need ideas though!
Old 10-15-06, 10:49 AM
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Any one got any advice? Could a vac leak cause the boost not to spool at all?
Old 10-16-06, 11:28 AM
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Boost Leak Test?

Ok, going to check for big **** boost leaks. Someone let me know if this is right...

Im going to buy a 3in PVC cap and put a shroeder valve into it.

Im then going to remove my air flow meter and replace it with this. I still have stock bov and ic.

While the car is off (or do I turn the key to make the electronics such as the stero and boost gauge turn on?) I am going to pressurize the system by hooking up a compressor and pressurizing it to about 10psi(however my compressor is in kpa so that would equivilate to 69kpa).

Then listen for leaks.

Afterwards depressurize and replace hoses.

Sound all ok? For any of the question marks, anyone got any answers? Thanks alot. Also if you guys have any advice for my questions above, that would be a great help.

Espec the one about what the little hose is that connects the uim to the engine.
Old 10-17-06, 08:57 AM
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Performed Test.....

Well, I made me a tester by dremeling a hole into a can of cream corn then smoothing the edges with the dremel. I then took a shroeder valve bought at oriellys and pulled it through. Also put some super glue where the can and valve met on top. Works great.....

HOWEVER, I need help. I was at first worried of running too much PSI. I put 25psi and phhh nothing went. So I let it build up to 75psi and ran it through, there was no pressure build up! I thought couplings were supposed to fly off or the wastegate would open! The compressor actually went through all of its air and had to refill!

So I am at a loss. I found a small leak on the coupler ontop of the turbo, but it sounds like all of the air just leaves from the tmic... I listened and then pulled the bov hose that connects to the throttle body. The little throttle body nozle had air coming from it, as well as the bov hose.

I did not hear any hissing, just air wooshing by. Any suggestions? Oh yea, again, does anyone know if the very short hose under the uim that connects to the engine passes air or coolant? Thanks.
Old 10-17-06, 06:46 PM
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Ok, well found three leaks. One was a weak tmic clamp, another was the coupler ontop of the turbo, and another was right behind it...guessing that is the acv. It was not the actual acv but a part that is attached by screws.

I sealed all of those up, but will wait until tomorrow to see about running her.

Question:
When pressurizing the system, should the turbo be functioning?? I have yet to hear the turbo spool or the wastegate open. The turbo is in good working order with no play at all. Nor has any amount of pressure really built up...

and also, I found that the hose under the uim is for coolant...
Old 10-25-06, 11:14 AM
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What do the spark plugs looks like?
Are they all BLACK?


-Ted
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