1993 gm3 turbo issue
 

Hi, I have a 1993 6.5l turbo mechanical IP, 4l80e auto 4x4. Upon purchasing the truck last month i noticed a lack in power when towing and lots of black smoke and random stalling. I could hear the turbo wistling. I found the inline fuel pump was shot and repaced it, that solved the stalling, made it run better but now hear no turbo anymore. So i installed a boost gage and get 0. I wired shut the wastegate and still Opsi. other than checking the waistgate itself for damage and the fins, looking for play in the shaft(which all seem ok) are there any other steps in checking the turbo? whats that tube going to gasser fuel pumb loctaion for?

check the vaccum lines going from the wastegate to the vaccum pump. im betting either your vaccum pump is shot or your lines are broken

93s dont have a vacum pump do they?

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even if i did would wireing the wastgate shut should by pass that function all together? last 6.5 i had i took it off and built a manual wastegate controller. no experience with the old school turbo

do you have a line coming from wastegate to the bottom of the serpentene belt?

no it is a sealed wategate accuator, the only line is a 1"ish hose going from the turbo to the block where the fuel pump is on a gas engine

well not enough air is getting to the engine so look for airway restrictions. ive heard about a pound of crap stuck in the intake manifold clogging it up

well, when i drilled out the intake manifold it was very clean. I even removed the lower part of the intake manifold to repair a leaky valve cover and checked for leaks, The tube on the bottom is the oil drain. Turbo is oiling. There must be a problem with the turbo. The wastegate is functioning as it should. Truck has 340 000 km so its old.

any play in the compressor wheel?

Thanks for all the advice! I cleaned and tighed down everything from the injector lines up and when I test drove and warmed her up the boost gage came to life! Pulled a steady 10psi and up to 15psi on heavy throttle. Spool up is slow but we will see what a manual wastegate does. I suspect it was working all along just need a bit of love to kick er in is all! I had difficulties finding a 15psi gage and had to settle with a 30psi one. A more accuate gage would have saved time.

thats good to hear. i dont like any of the boost gauges on the market. they either have ones that go up to 30 psi or ones that go up to 15 psi. i need one that goes up to 20 or 25