1993 Nissan Pathfinder Does not run correctly

OPIE007

MEMBER
1993 NISSAN PATHFINDER

Engine Mechanical problem
1993 Nissan Pathfinder 6 cyl Four Wheel Drive Automatic

I have a '93 Nissan Pathfinder, V6 on which I rebuilt the heads over the winter due to bent valves caused by a broken cam drive belt. I got it running (sort-of) in April.

The problem is it won't idle or even come close to it. When cold, I have to keep it a 3-4k RPM just to keep it running while pumping the gas pedal constantly. After it's warmed up, I can get it to stabilize at about 1800 RPM, far to fast to check the timing.

The odd part is that the cat-converter gets so hot and heats the muffler so much, it nearly caught fire the first time I warmed it up.

The car filled with smoke so I shut it off to figure out what was happening. It turned out to be the bottom of the back seat was scorched and melted from the heat that came through the floor panel from the exhaust system.

I thought the overactive cat-converter was probably caused by too much fuel in the mixture so I changed the O2 sensor. Waste of money. No difference.

1 Reply

MHPAUTOS

MECHANIC
31,938 POSTS

Hi there,

We need to do a few basic checks first as I feel that the basis of your problem is possible vacuum related or a faulty injector may be park of the problem as well, firstly can you please confirm that the vale timing is correct re check cam timing in relationship with crank timing, when you are sure that this is correct, check that there are no vacuum leaks in the induction system, do a scan to check for any unresolved fault codes, do this and post your results for further assistance.

Mark (mhpautos)