Turbo boosting 2psi only, stumped.
#41
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If the above doesn't work. How would I be sure the turbo is ok? Like I said before, I tried to clock it, but the c clips I saw I did not have a large enough snap ring pliers to get them apart. Plus all the rust and stuff, the thing would not budge. I suppose I could take it back off (holy moly what a pain) and pb blast the **** out of it. Maybe I can get it to budge.
Do you think if I take a picture of the housing you could tell if it's apart at all?
Do you think if I take a picture of the housing you could tell if it's apart at all?
#44
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I've not read all of this thread, but is it possible you've overlooked the wastegate actuator?
check for play on the valve lever arm. If you can wiggle it at all, it is too loose.
IF the actuator is set too loose, the boost can be way off, as well as very sluggish. IF the turbo has a turn buckle push rod, pull the circlip off at the valve end and shorten the rod until the turnbuckle hole is one diameter shorter than dropping onto the pin without any pull on the rod. THat should be enough preload to make 6 psi, or so.
If no turnbuckle, wire the valve shut somehow and drive it. IF this is the culprit, wiring it shut will eliminate boost control, so use a bit of caution.
corky
check for play on the valve lever arm. If you can wiggle it at all, it is too loose.
IF the actuator is set too loose, the boost can be way off, as well as very sluggish. IF the turbo has a turn buckle push rod, pull the circlip off at the valve end and shorten the rod until the turnbuckle hole is one diameter shorter than dropping onto the pin without any pull on the rod. THat should be enough preload to make 6 psi, or so.
If no turnbuckle, wire the valve shut somehow and drive it. IF this is the culprit, wiring it shut will eliminate boost control, so use a bit of caution.
corky
#45
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Ok, so I tied the wastegate open, removed the FMU, and took it for a spin. Full throttle at anything under 3k, the motor searches between 13.9-15.3 afrs. After 3k, it dumps fuel and runs an almost steady 11.5 afr. Now I have the 99-00 injectors in there, so that's understandable. But what I don't get is why it's surging at the lower rpm. Is because of the bigger injectors as well?
Any ideas?
Any ideas?
#50
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So, you've ruled out the following so far:
And you say it's not the turbo or the injectors.
As suggested earlier, run it with the catalytic converter/mid pipe off. It will be loud, but all you need is one run to see if it will build boost with an open pipe.
Which spot are you using as your signal line for the rising rate FMU? I've had good results with teeing off the stock FPR.
- boost leak
- wastegate
And you say it's not the turbo or the injectors.
As suggested earlier, run it with the catalytic converter/mid pipe off. It will be loud, but all you need is one run to see if it will build boost with an open pipe.
Which spot are you using as your signal line for the rising rate FMU? I've had good results with teeing off the stock FPR.
#51
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Yeah, I dunno. Like I said, I've had this car for a few months now so I'm still learning how the PO took care of it. It very well could be on its last leg. I don't think the knocking sound is in the motor though. I can hear it when I'm sitting the car, but not outside at the front of the car.
#52
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It was tee'd off at the FPR after I fixed the lines. They had like a mini vacuum block thing with about 5 lines coming off it. I didn't think that was good. I will have to see if I can get the bolts loose on the catalytic converter. If I can't I may just sawzall it off. Might be trying that today.
#56
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Extend the threaded wastegate actuator arm a little bit, but make sure that it's still pulling on the wastegate to keep it closed.
If it's too loose (too long), it will essentially keep the wastegate open or open prematurely, causing you to lose spool.
14.2 AFR @ 8 psi is dangerously *lean*. Once the FMU sees positive pressure, your AFR should start dipping into 13 and continue to get more fuel down to 11's the more you get into boost.
Fix/adjust that first.
If it's too loose (too long), it will essentially keep the wastegate open or open prematurely, causing you to lose spool.
14.2 AFR @ 8 psi is dangerously *lean*. Once the FMU sees positive pressure, your AFR should start dipping into 13 and continue to get more fuel down to 11's the more you get into boost.
Fix/adjust that first.
#60
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If not and that has nothing to do with it I will still make the arm longer.
Above question deserved that answer diesel, I was just too excited. Literally shaking, I held my hands out and they slowly started twitching, then onto full on seizure. Way too much adrenaline going, but so happy we figured it out.
Above question deserved that answer diesel, I was just too excited. Literally shaking, I held my hands out and they slowly started twitching, then onto full on seizure. Way too much adrenaline going, but so happy we figured it out.