Mechanics

ENGINE RUNNING REALLY ROUGH!!!!

2000 Nissan Quest

Engine Mechanical problem
2000 Nissan Quest 6 cyl Front Wheel Drive Automatic 125000 miles

alright, the car use to drive good when it was cold and then started jerking like if it giving out, then as time went on it started getting worse, it would start turning off as soon as you give it gas, if it didnt turn off it would just be running rough like a kid trying to learn stick shift with a heavy duty pressure plate, thats exactly wat it looked like and felt like, well whenever it turns off, it cranks right over no problem, like if theres nothng wrong, so that cancels out the distributor in my head, we changed spark plugs wires, fuel filter we checked fuel pressure, constant 35psi, the cat and manifold are getting cherry red so I thought clogged cat, so I disconnected the pipe and ran it straight pipe, still same thing so cancels out that, now im stuck, no check engine light, only knock sensor like every other nissan quest, so yea if anyone can help we would really appreciate it.
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Stumpedguy24
April 11, 2009.



Hi stumpedguy24,

Thank you for the donation.

When Catalytic converters runs hot, it means excessive fuel is getting to it.

Possible causes are : 1, Misfiring cylinder, could be spark plugs, wires, distributor cap, rotor, ignition coil. A weak ignition coil can cause misfiring under load.

2. Fuel injector supplying excessive fuel.

I would suggest checking if any cylinder is not performing correctly.

KHLow2008
Apr 12, 2009.
Ill check all that, but the last time I checked the car was running lean, spark plugs were white, but do you think if could be something in the distributor, because the car always turns back on, never cranks more than twice.

Tiny
Stumpedguy24
Apr 12, 2009.
The ignition coil is inside the distributor so it is possible. If the coil is weak, it would cause misfire and this would result in the symptoms described.

Under such circumstances, it might not cause difficult starting. As a matter of fact, I just encountered a similar case on a Honda. After replacement of the coil, which had resistance readings within specs, the problem was solved.

KHLow2008
Apr 12, 2009.