Misfires 101

pickup
nissan

#1

can a misfire cause a distributor to go bad.check engine light came on p.o302 number 2 cyl misfiring have replace distributor three time in one year, now it need distributor number four. 1997 nissan pickup 2.4 liter


#2

Much more likely that your scenario will be flipped: A bad distributor causing a misfire.


#3

A misfire can damage the coil. The coil is built into the distributor, but you don’t need the whole distributor.


#4

Whatever’s causing the misfire could damage something in the distributor too. Like on a pre-electronic ignition distributor there’s a capacitor there (usually called the condenser). If that part fails it can damage the ignition points, and also cause misfires. Since you only have a misfire on number 2, that seems like it would simplify things at least in tracing the problem if it is in the ignition system. You may have something arcing along that path. Or the spark plug is shorting out by carbon depsosits. Take a look at it. Then try moving the spark plug high voltage wires around maybe. Arcing is more likely if the high voltage wires are run in parallel, so see if you can arrange them to cross each other at 90 degree angles, see if anything like that helps. Idling the engine at night can sometimes show up arc’ing at flashes that you don’t see during daylight, so that’s worth a try. Spraying the wires with a fine mist of water with the engine idling can be diagnostic too. Look at the underside of the distributor cap, sometimes you can see little carbon tracks. If you do, that’s no good.

There’s other things that can cause misfires, un-related to the ignition system, but I don’t see how any of those could affect the distributor.


#5

You need to work your way back. Maybe a bad spark plug, plug wire, or hopefully not low compression in a cylinder.

With any performance problem I always run a compression test no matter the make, model. or miles. In some that are difficult to access the spark plugs a good alternative is a vacuum gauge for a preliminary check.


#6

Is your only problem a misfire in #2? If so, the distributor is NOT the problem.


#7

How many miles does this '97 have on it? Do you have any signs of a bearing knock?

The reason I ask is because I recently came across an old high mileage engine wherein a rod bearing knock was being detected by the anti-knock sensor as a misfire and the ECU kept repeatedly but occasionally posting a “cylinder 2 misfire” code.


#8

Nissan have 280,000 miles on it, have replace distributer three time.


#9

number 2 cylinder is only cylinder showing misfire,


#10

When the distributor fails, the truck will fail to start or run. If it is running, it does not need a new distributor. It might need a new distributor cap, a spark plug wire or a new spark plug or there may be a serious loss of compression in that cylinder or even a failing fuel injector, but it doesn’t need another distributor.

I’m thinking you need a new mechanic.

Do you hear any strange noises coming from the engine like lifter clatter or knocking sounds? Is the idle rough? Low power? Bad gas mileage?


#11

Maybe the failed distributor are a red herring. A misfire mean the computer is sensing the crankshaft is not accelerating after being pulsed by a spark plug firing & a power stroke like it should. You should be able to feel this happening when driving the car. Do you? For a cylinder to fire it has to have

  • proper gas/air mixture into the engine
  • proper amount of above
  • good compression
  • spark, and at the right time
  • ability to push the exhaust gasses out without restriction

You just have to go through each of those one by one. Start by verifies a good healthy blue-white spark at the number 2 spark plug.


#12

At going on 300k miles you really need to run a compression test. Otherwise you may beat your head on the wall forever.


#13

none of those problem. just will not start.


#14

That changes things.
Exactly what is it doing when you try to start it?


#15

If it wont start or run, then I’d look at the coil inside the distributor and not the whole distributor. If you are burning up coils, then you have to address the misfire issue. Misfires create a peak voltage that can lead to internal arcs which eventually damage the coil.


#16

it try to turn over. but wont crank my mechanic say it need a distributor 3 distributor in one year that crazy. using a after market distributor maybe I need a Nissan distributor


#17

Do you mean the crankshaft won’t turn at all or that the cranks turns but the spark plugs don’t fire?
Your other comment suggests that there’s no spark, but this comment seems inconsistent with it.

Does your mechanic suggest why he’s had to replace the distributor three times?
Have you considered trying a different mechanic?


#18

it turn over but wont crank. funny thing check engine light p.o 302 wont even come on while you drive around town. but if you go out on highway after about 20 mile it will set a code p.o302only at highway driving.


#19

OP says it turns over but won’t crank. Aren’t they the same thing ? At first I thought the starter would turn the engine but it would not run. Then he says he drives it. It appears there needs to be some clarification here.


#20

That is contradictory, turn over and crank usually mean the same thing.

My guess is that the OP means that the starter turns (cranks), but the engine won’t start.

Perhaps some definitions will help.
When you (on a working car) turn the key to the start position, you initially hear the starter turning, or cranking (whirr-whirr sound). After a second or so, the engine catches and starts running on it’s own. You then release the key and the starter stops.