88toypickup

My girl friend has a 1994 Nissan Sentra that isn't idling right and doesn't have any power. I have probably spent $400 on new parts and nothing has worked. I replaced the distributor (it was leaking oil anyways), cap and rotor, coil, wires, spark plugs, fuel filter, air filte,r oil and oil filter (not that an oil change would help, but I was already down there). I also adjusted the timing, checked valve clearances and tried to look for vacuum leaks. It still doesn't run right. So we took it to a shop and they couldn't find anything wrong with it, although I don't think they tried very hard, I think that they understood that if they diagnosed it, I was going to fix it and they didn't charge for a diagnosis if they didn't find anything. Anyways I am still not ruling out a vacuum leak or messed up timing ( I timed it in a hurry with a $15 harbor freight timing light), but any other ideas would be appreciated.

Sorry for the long explanation, but this is driving me crazy.

theAuthority

nissan, ewwww...

But I think you answered your own question. Re-time it and take your time, if it still runs bad get back to us.

Diagnosing is making a list of 'suspects' and slowly crossing them off. You've done a lot of work so far and thoroughly crossed things off. Why do half a job and wonder if it's the problem the rest of the time.

Let us know if the timing fixed it.

good luck

88toypickup

Thanks, I will try timing it again. The only thing that makes me wonder if it is the timing is that the engine is always kind of hunting. It will idle high for a little while, then low for a little while, then back to high. It never really finds a nice steady place to idle at. Maybe it is the timing. I guess I will wait and buy a better timing light, maybe one with a tachometer and I will start over and try again.

theAuthority

try and get some codes, even if your check engine light isn't coming on, there are probably some codes or past codes you could check out.

read up on this. I've read too much nissan already .. now I have migraine

http://www.extreme-check-engine-ligh...%20Decoder.htm

88toypickup

Thanks for the information. I will have to give it a try this weekend if I have time. In the Nissan's defense it is easy to work on for a front wheel drive car. My parents have a 1994 Toyota Corolla and we have this 1994 Nissan Sentra. I have replaced the clutch in the toyota and the throwout bearing in the nissan, and the nissan was a lot easier to work on. But then the toyota gets better gas mileage, has more power has a smoother transmissin etc., It just feels like a better car all around.

oldtrx

sr20 or ga16? i have a 91 and a 94, both have manual trans,ga16, anddddd idle problems. best solution i have found is octane booster. i remember reading somewhere about a vacuum operate valve that commonly goes bad but i cant remember for sure