#6 Interminent Misfire Code

[Tim Hampson]

Recently I brought my 2003 Mazda Tribute in because the Engine light was on and the car was running rough. The code ended up being #6 interminent misfire. When they got the car it wasn't doing it anymore so I decided to wait it out. Lucky I did.

About a week later the problem came back, the car seem to be missing. I brought it back to the dealer and there were more codes.

- Misfire on #1,#2,#3
- ETC out of range for test

As it turns out it was the Cooling Temp Sensor after all. They replaced that and all is back to normal. It looks like it was getting a wrong reading and messing up the fuel curve and making it look like a coil was misfiring.

Regards,

[AlohaBra]

Thanks for the info.

[Tim Hampson]

Ok, Maybe I was wrong.. It's doing it again... this time a few more miss fire codes and the dealer wants to replace 4 of the Ingition coils thinking that will solve the problem... Now I'm lost.. What else can it be? It can't be 4 Ignition coils going at the same time...

What does the computer look for when triggering an Intermitten Ignition coil Code? Could it be a plugged fuel injector?

Any suggestions would be helpful... Thanks!

Originally Posted by Tim Hampson

Recently I brought my 2003 Mazda Tribute in because the Engine light was on and the car was running rough. The code ended up being #6 interminent misfire. When they got the car it wasn't doing it anymore so I decided to wait it out. Lucky I did.

About a week later the problem came back, the car seem to be missing. I brought it back to the dealer and there were more codes.

- Misfire on #1,#2,#3
- ETC out of range for test

As it turns out it was the Cooling Temp Sensor after all. They replaced that and all is back to normal. It looks like it was getting a wrong reading and messing up the fuel curve and making it look like a coil was misfiring.

Regards,

[danielsatur]

I would try a out of car Injector service!
1) The injectors are put in a ultra-sonic bath,pressure cleaned,and checked
for flow rate.
2) Put a new gas filter in.
3) 1/2 can of Seafoam in gas tank.

Do a GOOGLE ''Out of car injector service''

A good diesel engine shop will have the equipment to clean injectors.

Good luck!
MCGIVER

[Tim Hampson]

Originally Posted by danielsatur

I would try a out of car Injector service!
1) The injectors are put in a ultra-sonic bath,pressure cleaned,and checked
for flow rate.
2) Put a new gas filter in.
3) 1/2 can of Seafoam in gas tank.

Do a GOOGLE ''Out of car injector service''

A good diesel engine shop will have the equipment to clean injectors.

Good luck!
MCGIVER

Mcgiver,

Thanks for the input, I'll try that if this doesn't work out. I put in 2 cans of Fuel injector cleaner (1 for each full tank) just after seeing your Message and I have not had the problem since (But now that I mention it, it will probably come back.. Ugggg). So for now, it seems to have licked the problem... Let's hope that was the problem.. maybe a Bad tank of gas clogging up the injectors, causing those wierd error codes?..

Thanks again

[AlohaBra]

so..to clarify...the engine light went out?

[Tim Hampson]

Originally Posted by AlohaBra

so..to clarify...the engine light went out?

Yup, After the misfiring stops for a while, the check engine light turns off.

Regards,

[dashmore]

I certainly hope your issue goes away and stays away, but I'll explain how the system reads a misfire code on a coil pack. A coil has a certain amount of resistance in the wiring, it will vary from model to model. The computer reads that resistance and typically it has to be with in ten percent of the known value of a good new coil pack. It will read the value at start up as a self check and reads the value each time it sends a firing signal to the coil pack. It does this simply by knowing the amount of power (the load) that should be on the line when it sends the fire signal. If the load is too high (shorted) or too low (open) it will register the code. Keep in mind that is all it can read and give an accurate code for a paticular cylinder. Once that part is done the coil pack and the spark plug do the rest and there is NO WAY the computer can monitor an individual cylinder firing condition. For example, you will never get that code for a bad spark plug. The exhaust sensors look for conditions of the exhaust gases but can not determine a specific cylinder problem. I hope this makes sense enough for me to say that it sounds like you have had an electrical problem that is intermittent.