fasterbbc

alright so I finished swapping in the LDK engine and that is all good, but I am not getting any boost. When the previous engine blew I noticed the boost was bouncing between 10 to 25 psi then the rod and pistons decided to make a window in the block. before installing the new engine and a TurboBay Performance upgraded turbo, I flushed and cleaned the oil lines and the intercooler. all gaskets are new. the only sensors swapped over were the Charge Air Bypass Valve Solenoid and the Turbocharger Wastegate solenoid. also the Charge air bypass valve.

I have verified there are no leaks in the boost circuit. Also everything is connected correctly.

on initial start up the Turbo Howls until the warmup high idle comes down. during this time the turbo has a buzz to it as well. After warmup and driving when I would normally be getting boost you can hear the turbo whirl but no boost.

there are no codes and I verified I didn't leave a rag stuffed into the cooler. I am at a complete loss as to what the issue is. Is there any way to check the 2 sensors? meaning can I jump the vacuum lines, if so which ones. Any help would be great. thank you

RJ_RS_SS_350

There are a few things it could be. Maybe the vacuum tank got damaged, I think you can test by bypassing it, hooking manifold vacuum directly to the bypass solenoid. Or you could plug the port on the solenoid(or the line from the tank to the solenoid) and pull a vacuum on the manifold line, see if vacuum holds steady(this will probably give you more conclusive results).

Or your bypass valve could be stuck or damaged. Or your bypass solenoid could be bad. Or the turbo could be bad. Or the wastegate could be stuck open. I don't know what to make of the turbo howling and buzzing and all that.

Boost was bouncing between 10 to 25 PSI... Do you have a tune? i.e. is 25 PSI normal for you? Was it bouncing with steady(full or part?) throttle?

fasterbbc

thanks for the response.

Testing so far:

bypass valve is good
- waste gate actuator vacuum line on hooked and plugged - no change
- pinched off the vacuum line to the Bypass valve to see if that actuator was stuck open - no change
- pulled the intercooler outlet hose and there is air being pushed through at idle (all though keeping it running is difficult)
- the inlet side of the turbo spins freely (trying to find the buzz)

Questions:
should the waste gate actuate during startup/warmup phase
this is bone stock accept for now the Turbobay upgraded turbo and LDK engine. so the bouncing boost was 100% stock, motor went while in 3rd at roughly 4500rpm.

next: I will try bypassing the vacuum tank (didn't see any damage when swapped over)

celblazer

Any Codes? Possible boost leak? Triple check all your pressure piping and fittings. I could see a leak buzzing under the right conditions. It's also easy enough to build a home pressure tester for a few bucks in parts from the local hardware store.

fasterbbc

I did a boost leak test supplied 25 psi to charge pipe holds 23.

No codes

donbrew

I assume from the wording that you tested with the valves in the circuit.

If the tubing hold pressure, what could be the cause of low pressure in the system? Basic fluid dynamics would suggest the pump that supplies the pressure.

fasterbbc

Yes I tested with everything else in the circuit. So complete system. I certainly question the turbo. I don't like the noises it makes if nothing else. What is the best way to force test the turbo meaning bypass all the switches. I can handle not over boosting with the gas pedal. Only to diagnosis the issue. Would love to rule something out.

Oldblue

I'm thinking if you have the turbo off the new engine , bolt it up and try that!

fasterbbc

I only have the one turbo other one was returned for core to which I am still waiting on core refund.

Oldblue

Well there goes that idea! Lol