hi everyone im a newbie to this forum and to working on cars.im having problems with my 91 gta lb9 engine.the car wants to and does stall at red lights and rpms seem to be acting irratic unless i put the car in neutral.also my oil pressure used to go up as i accellerated and then down to zero.now it just stays at zero.any info would be EXTREMLY appreciated.

 

the first thing that I would do is see if the oil preasure sending unit is bad. take it out and put a preasure gauge in the hole and see if you have oil preasure.

If you do not want to do that make sure that the engine is not ticking and knocking.

Still you want to replace the oil sending unit soon. It is located on the drivers side of the engine block above the oil filter

 

thanks ill try that,whats messed up is today i had it out and pressure gauge seemed fine.a little low but fine.still cant figure out the stalling though.i cant stop at a red light without putting it in neutral and even then it idles low unless gas is pressed a little.

 

Your idling problem sounds like your IAC is bad, out of adjustment, or dirty. Or there is a vacuum leak somewhere.

 

yeah, i'd say a vaccum problem before the IAC. look around your engine bay for broken vaccum lines, or sounds like SHHHH like loud, you know? and just try to follow the sound and fix the problem. (when the car is running of course)

 

i had the same..... well have the same problem with mine... the intake manifold is leaking in the back id say check that too

 

i'd doubt it was leaking in the back, unless the thing was put on defectively, i mean what you have is probably a vaccum problem man. its very weird to be getting a manifold leak towards the back where there is no coolant flow. i'd check around for vaccum lines cracked, etc.

 

thanks guys i kinda figured a vacuum line was leaking so ill check everything you have suggested. everyone has helped out alot and ill let ya know how the check up goes!!thanks

 

no problem man, let us know how everything goes. GOOD LUCK

 

well i found out what one of the main problems was for my car stalling at the red lights today.i shoulda thought of it first but like i said im new to the car repair thing!! lol It was my timing,it was off by like 3 inches!!but i do have a leak in my intake.so thats got to be fixed and i found a couple lines that were vacuum leak hazards because they were real dry.i put a tester up to them and no leak so far.also i still need to check my oil sending unit,the gauge is showing no pressure after about 10 minutes of driving.

 

did u disconnect the EST wire on the pass strut tower when u set the timing?

It should be a tan wire with a black(i think) connector on it.

U have to disconnect it to set the base timing as the ecm otherwise controls it. U unhook it and set the base so the ecm "knows" where the timing is set "base"

There are tech articles here on the main page to help u out with the basics.


Also recommend u go ahead and follow the IAC and TB cleaning procedure which is also there.

later
Jeremy

 

yeah i disconnected the tan line to check timing and it was still that far off!! my next thing is the vacuum leak on manifold.but im still not stalling anymore after the timing was fixed so im good on that for now.i need to check oil pressure still too.ill check the article you were talking about too.

 

i had the EXACT same problem w/ my oil pressure sending unit, it would go to zero after like 10 min of driving too haha, i wouldnt worry about it, its probably just a bad sender. when i put my new motor in with a NEW sending unit, the problem was fixed. i would just replace the unit, im sure your pressure is right where it should be

 

i kinda figured it was the sending unit,i havent had a chance to play with it lately but least ya reassured me a little so i wont worry so much.i REALLY dont need a blown engine from lack of oil!!!i also have to fix manifold vacuum leak still.i put tester up to it and found that it was leaking all the way around it.so thats gonna be a job in a half i think.