Engine/Transmission (1994 - 1998) Low power condition

[#crnxr]

Was experiencing a low power condition and heard the squeal of turbo going out. So I replaced the original WHC-1 with a PDRHX-40. However, the low power condition still exists. RPM's used to reach 2900 or so, but now the highest I can get is around 2000. I can barely hear the turbo spool up. Pretty sure its a shortage of fuel, but I don't have a guage. Lift pump was replaced about 6 months ago. The engine doesn't seem to be missing, and there is no smoke. Injector pump? Please give me some ideas to look into. Thanks.

 

[Joe G.]

If this engine is a 12 valve with a P7100 pump I would check the timing. Sounds like it has slipped.

 

[Tom C]

might check the boost line that runs from the AFC to the turbo actuator for holes. especially where it goes through the exhaust manifold. Mine had rubbed through in that area and would not allow the system to fuel properly. Thus leaving me with a top RPM of around 2100 (while driving) and no smoke. I fixed the Metal line and now she fuels correctly with plenty of smoke. If you can get your rpm's up to red in neutral but not in gear it would appear that you have a boost problem.



Hope this helps



Tom

 

[#crnxr]

Thanks very much for the help. Yes, even though the engine is from '92, it's got the P7100 pump. I think I've found the pump timing TSB off of Fritz's page (Thanks Dave). The problem is very consistent, regardless of gear - just seems to be in slow motion. Going to install boost guage this weekend to verify pressure levels. Thanks again.

 

[drees1]

Verify full linkage travel so the breakover lever on the pump is moving before full foot pedal is reached.



Check fuel pressure at hi and low idle.



Check wastegate boost lines as mentioned.



Check wastegate linkage to be free and not stuck.



Check air to air hoses for tears or loose clamps.



Pressure test aneroid on pump for blown diaphram or leak.



If your 92 engine has the timing pin in the cover pin the engine and pull the plug in the pump to visually verify the timing is close. (quick and easy to do, 15 minutes)



You heard a whistle or shrill noise when it happened, that is consistant with an air leak. What did you find when you inspected the first turbo as cause of failure or failed items? Shaft failure? Wheel failure, hot or cold side?? Although rare, a cold side wheel burst at speed could puncture the intercooler. If the cold wheel failed or burst have the intercooler pressure checked.

 

[#crnxr]

When I took the old turbo out I found the exhaust side blades touching the housing (?). There was no free play for the exhaust blades to spin, so I'm pretty sure this had caused the turbo to seize up and make that squeal sound. Intake side looked ok. Didn't have a wastegate, so I plugged the PDRHX-40 with a pipe plug. When I checked the intake air path I found some abrasion marks on the line from the intercooler to the engine, but not worn through yet. Guess I won't know for sure until the boost guage goes on. Thanks for the other ideas. Will check diaphram and throttle linkage as soon as possible.



-Kyle

 

[#crnxr]

Well, thanks to your ideas I found the culprit. The problem ended up being a loose throttle linkage. I was able to manually actuate the throttle and reach redline, but because the lever attached to the throttle cable was loose and slipping around the fueling pin, the go pedal wasn't doing much. Once I tightened the coupling the pedal response returned and it roared back to its old self, but even better now with the sweet whistle of the PDRHX-40. Thanks again.



-Kyle

 

[Tom C]

Kyle, Great to hear you found the problem. funny how some of the simplest problems are the hardest to resolve



Tom C