my 2001 nissan sentra is misfiring, what is the problem?

Question

the code reader at autozone said the car was misfiring in the 4th cylinder. i replace all the plugs but it didn't help. what else do i need to check?

Answer 1

1.8 or 2.5 liter engines can experence head gasket failure. You can see coolant leaking into cyl's when you pump up the radatior with a pressure tester put about 15 to 17 psi remove the spark plug from #4 and watch coolant run into the cyl. I use a light that can shine down the spark plug well a good flashlight can illuminate the top of the piston pull #1 cyl too so you can see a dry one. The misfire only occurs during start up some times the customer only says the coolant tank is getting low and engine light is on. Most cases head gasket is all it takes some times resurfacing the head is necessary.

Answer 2

Replace the spark plug wires. Contrary to what some "master mechanics" think, code readers detect electrical and electronic issues, not mechanical ones. Their readings come from sensors and other monitors. No code reader on the planet is going to detect a blown head gasket. Spark plug wires come in a complete set. Spark plugs are less likely to make a car misfire than bad wires. Wires deteriorate over time from heat and vibration. One rule to follow: Remove and replace one wire at a time. If you take them all off at once and try to put them all back on, you might get them on in the wrong order, then your problem will be worse.

Answer 3

the wire? If it seems to be giving spark the same as the others, then maybe do a compression check of the entire motor and compare results. If that cylinder is really no different than the others....then the problem is still electrical or fuel. delivery.

Answer 4

ive seen fuel injectors go bad on 00 thru 02 sentras alot.
head gasket leak is good to check for also, mostly you will see that on start up. fuel injector ground go bad all the time on nissans. nissan master tech also.

Answer 5

umm.. first off there is not enough information to make a correct diagnosis. take it to a CERTIFIED MECHANIC who will CHECK ALL parts that can cause this.