Weird Missfiring I have a 1999 Cherokee and it ran perfectly until a few days ago. I've been experiencing problems with is missfiring. However, it only happens when i hit a bump or turn left. It acts like it want to die and cuts out when any of these two occurances happen. And it even happens when i have a full tank of gas so I dont believe it is becuase of a low gas level. Any help would be great. Thanks

you cannot change oxygen sensors from front to back as they are 2 completely different units doing completely different jobs
the problem is water in the electronics and you use a dewatering fluid ( wd-40 or like ) to disperse the water not starter fluid

You seem to have covered almost everything electrical. That leaves mechanical. Either valves sticking, frozen, or spring, cam broken. Fuel line or injector to that cylinder is the only other item I can think of. Let me know how it works for you.

I would be concerned about sediments in the fuel rail. The fuels we use these days cause a lot of corrosion.

I think that you have an air leak. The fact that you hear it when you press the accelerator rather than when you release the accelerator suggests that it is outside of the throttle valve. Check the rubber boot/elbow that fits on the throttle valve. I just had to replace one on an '04 325 yesterday because the rubber was cracked.

Check for sticking idle air control valve and stuck open EGR valve. Both are common causes for very rough engine operation due to fuel-air ratio being too far off. Also check for large vacuum leak such as from rubber hoses connecting PCV valve to intake. Feel around for squishy or oily rubber which would indicate a leaking hole in the rubber hoses.

check new spark plugs for proper gap.
It may have gotten hit when installing it.check coils second for resistance/firing. sometimes one bank will work fine and the other side will misfire-always replace all together or as a unit. Check
engine for compression if problem pre existed
and check for low compression. if 1 cylinder
has 120 psi and two havepsi below 90 you may have
a cracked head or bad head gasket.

do you have a seperate coil for each spark plug check ur coil for number 6 or fuel injector

do you know the firing order? if not check it and re configure the plug wires to that order

hello,good day,hoping your car is already scan with hht or star,then engine missfiring very general,you have to check fuel injection and ignition system,hoping your fuel system is clean,if your tester appear your cly.8 coil is defect,try to put cly.8 coil in other cly.for testing purpose,hoping your engine is v-8,119,or 113,or try to check the pressure diapram in fuel rail,ty

Hi.....

The code P0302, Missfiring detacted at cylinder # 2.
The Code P1313, Catalystic Damaged Bank A , due to Missfiring.
The code P1000, Transsmission check Not completed. during test.

OK. The Important of this problem is, Check the Engine compression on the Cylinder 2.
If the compression is GOOD, Maybe you cen solve the problem Making a TUNE-UP.
But if the compression is LOW, You will need to spend Mony to REBUILT THE ENGINE or HEADS.

OK.. The catalystic come Damaged due to the Missfiring, And will need to replace.

The code P1000. You need a transmission compatible scanner to see if there a code on the Trans.

OK... I hope this help on your question


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