My car is running too lean.

[Drop Top]

OK Its an 87 G/N. I've had it about a year now. I did all the things that was sugjested to tune it up when I got the car. Including putting on all new vacume lines. Its all stock and ran very well after I welded up the headers and replaced the cat with a high flow and the down pipe with a 2 1/2 manderal bent one. I modified it very slightly. Ported the inlet bell, put on the K&N breathers, put a K&N air cleaner inside the stock housing and drilled some holes in the housing to alow for more air. I also replaced the fuel pump. Ran very well for me for a few months. Then the MAF failed. Replaced that and no more troubles. About 3 months ago it started to Idle ruff and the check engine light would come on. It would also spit back through the throtle body and bog down if I steped on it too much. I replaced the fuel regulator with an adjustable one. Uped it 5 psi from what it was before. That helped the idle but it still back fires. It runs much better in the mornings when its cold and still in the choke mode. I took it to a friends smog shop. He put his computer on it and said its running way too lean. He sugjestsed replacing the O2 sensor because it showed it to be weak. I did that and it didn't help it. Another macanic friend of mine sugjests replacing the MAF again. Theres nobody around here that knows much about these cars. So before I start replacing everthing under the hood I though I would ask all you people here. Thanks for your help in advance. When its running right I can't make up my mind wheather to drive it or my GTX. There both fun and about the same power wise. I have to admit the GN is more comforable.

 

[Drop Top]

ttt

 

[suicide six]

Do you have any readings from s/m etc.. any knock readings? Mine was recently indicating lean,but no knock. Turned out to be the grd wire stud on passenger side head backed out and was hitting firewall. Several grds on this stud and can be seen better from under car.

 

[speedfreakv6]

are there any g.n guys around you that would let u use there scanmaster or scanner to see what 02 is reading .is the check engine light on????best thing to do is buy a scanmaster or something to get live readings of what car is doing .plus it makes it alot easier to tune.

 

[XLR8]

Need input/scan tool readings. I would replace the fuel filter and check for vacume leaks though.

 

[acoen]

Sounds like a MAF problem, do know of anyone close that will let you borrow theirs. Check your inlet hose for cuts or holes. You are close to where I live but yet still so far away....I live in Fresno.