Sudden Misfire problem???

[criz067]

The other day I had driven my car (2002-V6) for about an hour and everything ran perfect. I parked it for about 2 hours and then suddenly on start up it started shaking and threw up a service engine light....I checked the code and it is a misfire on cylinder 1 only. The car runs fine at constant speed on the interstate but lacks a lot of power and hesitates when accelerating.

Sooo, I ran some gum out stuff on one tank of gas (didn't help), put a can of seafoam in a different tank of gas (didn't help), then I just replaced my spark plugs and spark plug wires, valve cover and intake manifold gaskets...annddd it is still misfiring.

Now when I pulled the cylinder one plug it was a bit oily and didn't look great and none of the other cylinders were. So I thought that at least changing the spark plug would temporarily remedy the problem even if the oil contact would foul it a while from now.

I guess oil is getting into that cylinder either past the valves or the piston ring but even so I wouldnt think that would cause my car to run perfect one minute then like crap the next.

The only thing left I can think of is there is something wrong with the fuel injector. Since just one replacement fuel injector is a bit pricey, is there a good way to check if it's bad without buying another one.

Any other ideas???

Thanks

[ezekiel.glnt]

i knw its alotof wrk,but one thing u can try is switching the no. 1 injector with say no. 5 injector and see if the misfire changes cylinders.

[Rob21]

+1^^^ try that and let us kno.

[criz067]

Okay....so I took out the fuel injector for cylinder one and swapped it with the fuel injector for cylinder 6. I put it all back together again, took it to AutoZone to get the code checked and now the code is the P0300 random misfire code. That is not at all what i was expecting to happen....soooo yeah i dont know.

I have sprayed starter fluid around the vaccum lines and intake manifold to check for leaks and I didn't notice any problems. The only thing I can think of that I haven't done is to change the distributor and rotor.

Any other ideas?????

[allrice4g64]

did you clear the code?

[ezekiel.glnt]

Okay....so I took out the fuel injector for cylinder one and swapped it with the fuel injector for cylinder 6. I put it all back together again, took it to AutoZone to get the code checked and now the code is the P0300 random misfire code. That is not at all what i was expecting to happen....soooo yeah i dont know.

I have sprayed starter fluid around the vaccum lines and intake manifold to check for leaks and I didn't notice any problems. The only thing I can think of that I haven't done is to change the distributor and rotor.

Any other ideas?????

yeah clear the code if u havent already and chek the spark plug wiring.also how is the car running?

[criz067]

Yes I have cleared that code....that's how I know that I have a new code. I actually cleared it twice.

Yes, I replaced the spark plug wires as I stated in the first post along with my description on how the car is running. So if you could just please read that so I dont have to go over it again.

[machvali]

I had the same problem and same code does the car run fine when its cold? if so i would replace the distributor thats what i had to do

[criz067]

I had the same problem and same code does the car run fine when its cold? if so i would replace the distributor thats what i had to do

Well I just finished replacing my distributor cap and the rotor.

[criz067]

Update: Turns out it was the distributor cap that was the problem. The main center contact that touches the rotor had broken completely off!!! I don't know how the car was running at all.... I guess it was just jumping the gap! Good to know it wasn't anything too serious.

[AktionCat]

Update: Turns out it was the distributor cap that was the problem. The main center contact that touches the rotor had broken completely off!!! I don't know how the car was running at all.... I guess it was just jumping the gap! Good to know it wasn't anything too serious.

this just happened to me exactly an hour ago..I filled up for gas..stopped about 1 mile around the corner into the neighborhood stopped by 1 house couple blocks from mine..turned off car..then turned back on and starts putt'ing..got the code check and i had misfire on 2....somethings going wrong :<

How'd you find out about the distributor?

[criz067]

this just happened to me exactly an hour ago..I filled up for gas..stopped about 1 mile around the corner into the neighborhood stopped by 1 house couple blocks from mine..turned off car..then turned back on and starts putt'ing..got the code check and i had misfire on 2....somethings going wrong :<

How'd you find out about the distributor?

I just took off the distributor cap and saw the main contact point was broke. It is not hard. You just have to take out the intake tube, battery, and battery tray. Then there are only three small screws holding the distributor cap on. The replacement cap i got from AutoZone required me to get longer screws because the original ones didn't go all the way through the cap.

Make sure you keep track of where the wires connect to the cap by marking them or something so you don't mess the firing order up. I accidently did that at first and it didn't run well until I caught what i did.

[AktionCat]

Edit: Fixed