What a way to spend a vacation ...

Had the timing belt, tensioner, water pump, cam and crank seals changed on the Maxima. Job was finished, and the car ran fine.

Later that day, engine started missing. Took it back to mech's this morning - running rougher and rougher. Checked, and changed plugs, rotor, dist cap (boy - how did it *ever* run with that thing in place?), and finally plug wires. Ran fine for 2 mins, then started running rough again.

Stopped the car - came back 5 mins later - she's running smooth as a baby's bottom. Driving around, went over some RR tracks - starts running rough again. Stopped, did an errand, came back, car's running fine again - and continues for about 30 mins, with a couple of stops on the way.

On the way home, went over some bumps, and she's rough again...

I'm thinking something electrical is loose or broken - maybe injector wiring? maybe a ground? I was thinking that the belt slipped a tooth earlier, but that doesn't explain why it ran smoothly later...

Ideas?

Michael

 

I'd start by going back and checking that everything is torqued to spec and all connectors are on tight.
but your problem does sound electrical in nature, it's gonna take lotsa time to diagnose though, unless you just wanna throw parts at it

 

does everything need to be torqued to specs like the FSM says, or can you let it slide on most things? its just i find it nearly impossible to get that damn torque wrench in tight spots.

 

Im thinkin electrical also. I would start by checkin all the electrical connections and grounds that are around the area where the work was performed. Maybe a coolant temp sensor wire was hit and weakened, or a coil wire, or something of that nature. Good luck

 

I had dat problem to, when I thoght the belt was tight the tensioner wasnt keeping it in place and everytime I went to start it, it would idle rough and the timing would jump. If you wanna do a quick check to see if the timing is out, advance it slightly at the distributor and see if it gets better. If it does, take it all down and redo it.

 

Well, it appears that the middle injector on the back bank is pooched. 0.0 ohms resistance isn't a good thing, is it? Funny how it would work and then not work, though...

 

i had one of my injectors do that to me a few times.
there is hope that it may start working again by itself, but be prepared to eventually replace it when it decides to fail for good.
also when you do replace it, I HIGHLY recommend replacing all 6 with new ones, the rebuilts have a very spotty track record.

 

Do the tensioners get noisy, like a bad lifter when they start going out? Or do they just strand you?

 

Should have added, the car is a 94 with 190000miles runs strong, just noisy over the last week.