Hello. Recently I started having issues with my 2008 grand touring. I left for work the other day and it was very rough and had little power. The check engine light started blinking, I returned home as I was not out of the neighborhood checked fluids and everything was fine. Started it back up and it was fine check engine light was solid but car ran fine. Ran the CE code which was P0304 missfire in cylinder 4. No more issues the rest of the day so we replaced spark plug. Same thing happened the next day. Swapped the boot to see if that was bad still was in 4 the next day. Checked the spark plug the next day for moisture and nothing so we don't think the head gasket is bad also oil is fine not milky and coolint is fine also. There is 86k on the car. Any suggestions on what it could be from here? Thank you in advance.
Rough engine
- Thread starter Rexer66
- Start date
It only runs fine after the car runs for a while so in the morning before work I start the car then go in and get ready for work so it idols for about half an hour then on my lunch break I go sit in the car and let it idol it runs rough at idol for about 20 minutes then it's fine. Then when I go home at the end of the day the car stars fine and acts normal but in the morning it's rough and at lunch it's rough.
Most of the time the car will run fine. This usually happens under load. When the first coil went out I would get a misfire when I would accelerate going on an incline, then it would just stop flashing when I would be on level ground. The second one happened when it was raining and the engine also under load when I would make a turn and give it some gas. The second coil was replaced along with the plugs and so far no problems. When I took it out the shop the first thing I did was drive it hard and take it up hills and drive it with the a/c on to see if the problem would come back, but so far so good.
. I know what your saying but we switched the coil from cylinder 4 to another and the next day when I started the car and the check engine lite came on I checked the code and it said it was still cylinder 4 by switching them wouldn't it throw the code in that one instead of 4?
Quick update I took it to advanced auto and there reader found more codes so the three codes are...
P0174 bank 2 system to lean
P0204 injector circuit open cylinder 4
P0304 cylinder 4 misfire
This sounds like a bad fuel injector what do you all think? If it is, worst part is no one has it and earliest I can get it is Thursday.
P0174 bank 2 system to lean
P0204 injector circuit open cylinder 4
P0304 cylinder 4 misfire
This sounds like a bad fuel injector what do you all think? If it is, worst part is no one has it and earliest I can get it is Thursday.
veyl_oiuja
Member
- :
- 2007 Mazda CX-9
My 6th cyl is misfiring. Was the replacement part better or would there be a chance that it would be bad again?
Mazda replaced the # 6 one under the extended warranty. It has been 31k miles since the replacement. Recently no. 2 went out and that was replaced by the indy mech who also replaced all of the plugs since that coil was in the back and he recommended it being that everything was accessible at that time.
