I have a 1992 maxima se which had been running rough and failed smog. Took it to a local mechanic and he said fuel injector was bad. This was replaced and mechanic mentioned it was still failing smog and thought it was a o2 sensor. Once completed it was an erg valve, or sensor, not o2. Now to the problem. Prior to this I never had a start issue. Now it starts intermittently, with no real pattern. Sometimes it starts with no problem, drive it a bit, then it won't start. The engine just cranks and cranks... Other times it won't start, but go back later and it does. I noticed that once started the rpm fluctuates pretty bad when in neutral or park 700rpm to 1500rpm. Once in gear you don't notice anything though... Brought it back to the mechanic and he cannot determine the cause. He says it has happened but he cannot determine the cause. I asked if it was related to the recent repair and he says no. I want to believe him but it seems like a big coincidence that I have this problem after spending $$$ on an injector. Any advice we be appreciated.

 

Vacuum leak or Coolant Temp Sensor. Given that its intermittent, personally I'd lean more toward a Coolant Temp sensor. Could be coincidence that it is crapping out more blatantly after the injector replacement. Mine **** the bed after I replaced fuel lines - a totally unrelated task. Purely coincidence. Easy to test if you've a multimeter.

 

Clean throttle and maf sensor

 

Thanks for the replies. I'll pick up car Friday and check those things.

 

Any update?

I had a flaky issue i'm pretty sure it was my starter but also leaning toward issue with the factory security.

Only happen when the doors were locked then unlocked with in a short period ie grab a slurpee once = stranded in the parking lot smashing starter (which did eventually work)
However looking back at points I disconnected and reconnected battery once or twice for undetermined amount of time.

Turned out my starter was pooched since I beat it to death (since test light showed power everywhere but off anything to do with starter in any key posistion)

Reason I bring it up.
I've had one occurrence since then which a couple lock unlocks of my doors seemed to clear.
Hence my theory security does have an immobilizer does it not?