How to check stock turbo????

[tskdave]

Dave here, fianaly got the 85 gn running..... I need to check if the turbo is working, everything is stock. Changed every sensor on car. not getting any boost. I took the "Y" restrictor out, went straight from the turbo to the actuator.....nothing. I thought this was suppose to give 12 lbs boost???? I checked the actuator with a compressor ....it does open. Any other way to test??? any ideas???? I can hear it whistling, but no power. I do have a after market boost gauge. Checked FP that is good also, cant seem to find any vac leaks or exhaust leaks. Thanks in advance.....DAve

 

[Jerryl]

Dumb question.
Where is the boost gauge connected?

 

[tskdave]

I was told to tie into the vac line going to the fuel vapor canister....with a tee... Shouldn't I have some boost?????

 

[buickpower]

Is your car in park or in gear? It probably wont build much of any boost without load, i.e. in park. Put it in gear, foot on the brake, and slowly rev it up. See if that gives you some reading.

JMO, but that doesn't sound like the best place to try and get a boost reading. The pipe plug at the front of the intake behind the fuel pressure regulator is a good spot, or some tee off the nipple on the back of the intake.

 

[FWD turbo]

I was told to tie into the vac line going to the fuel vapor canister....with a tee... Shouldn't I have some boost?????

If you have your boost gauge T'd into the vacuum line going to the vapor canister, you are never going to see any boost on the gauge no matter how much boost you are making. That line runs from the vacuum block on the throttle body - it NEVER sees boost. Only vacuum. At least not on a Hot-air car anyway.

Also, check your wastegate and make sure it is actually closed, and fits over the hole properly.

 

[tskdave]

I have tried it in park giving it gas .....no boost or so my gauge says. I have checked the gauge, it works fine. I thought all/any vac line would work??? Should going straight from turbo to the actuator give me 12 lbs???? Should I tee my gauge in there??? Thanks for all the help, I appreciate it. Dave

 

[tskdave]

o.k., just went out and changed the boost gauge line, found the port on the intake......just like you said . Guess what .....it is getting boost!!!! It will go up to about 10-11 lbs. Now the next problem....it is running terribly rich. Blm's are pegged at 150 at idle, at about 800 rpm. Goes down when you start to accelerate. If you go into the gas easy it goes pretty good, as soon as you step on it nothing but black smoke out both tail pipes. Studders real bad of the line, like it wants to stall. Heres what i've done so far: checked fp, goes up with boost, new maf sensor, new fuel filter, new regulator, new plugs new wires, new coil pack, new moduale. I'm running out of ideas, I dont know what I would do if this site was not available!!!!! Thanks again, Dave

 

[Jerryl]

What is the FP set at?
Did you do the spring cleaning and set the TPS and IAC?
Is this the correct chip?

 

[tskdave]

fp set at 38 idle , tps set at .42 iac bouncing around 15-35. I have hunting this problems for months, New stock 85 chip also. O2 sensor is about 2 months old. Cross counts seem to vary quite a bit 15-30. Could I have a pinched fuel return line ???? just throwing out anything....Dave

 

[buickpower]

With blms that high, I would definitely double check for vacuum or exhaust leaks. Your car is actually running lean, and the computer is attempting to correct by adding fuel. Were Blm's pegged before you installed the boost gauge in the intake, and is it possible that connection is leaking or you knocked a line loose? Also what maf sensor are you running with that 85 chip, and is it an 85 computer? You could also try turning up the FP a bit to say 42 or 43 just to see how that change affects blm's. keep us posted.

 

[tskdave]

BLM'S were pegged before, running stock Maf and computer. Also have no mufflers, open cat. Someone told me when you dont run mufflers, you need to increase fp???? is this correct??? Is there any way possible it is running lean and still putting out black smoke???? The exhaust system is covered with soot. Also gas milage is horrible... Dave

 

[buickpower]

correct, when you open the exhaust the car will lean out a bit, and you will have to bump up fuel pressure. If the O2 sensor isn't lazy, it almost sounds a little like incredibly late timing. Is the cam sensor set correctly? So you are running an 85 ecm correct, not an 87? and is your fuel pressure gauge known to be good? Also, do you know how much vacuum the car pulls?

 

[buickpower]

you are checking fuel pressure with the vacuum line removed from the regulator correct? still wouldn't explain the blms though..

 

[alec296]

black smoke

i have what seems like the same problem since my turbo went out and put a used one on .i noticed my adapter cone looks cocked and i cant get it to striaghten out. i hope this is my problem but there must be something wrong with turbo for the adapter to be coked so im going to get a rebuilt turbo but im thinking something bigger that a ta33 since i have a lee th 3in dp and atr headers and hooker 87 exhuast.
andy