Cylinder fouling AGAIN

[MrsZR7]

I don't think I've ever mentioned this before, as it's always been pretty easy to diagnose the problem....but it's getting repetitive. I drove my 2003 P5 across town yesterday morning until about noon without any problem at all. My daughter came over to visit, and we needed to run to the store. So we got in the car and noticed a very rough idle. It was shaking and seemed like it was going to stall at low RPMs. A familiar symptom with a familiar problem. Cylinder 2 misfire. We switched the coil packs, and then it read cylinder 4 misfire.
The thing is, I just replaced the plugs and wires at some point last year, and I know I've replaced the coil packs, plugs, and wires since I've owned the car in the past 4 years. This seems like a too-frequent maintenance thing, but this keeps happening! For the record, I get the oil changed pretty regularly and I don't drive it hard (other than general speeding...not racing kind of driving)
Could this be a sign of something major being wrong?


Sent from my iPhone using Tapatalk

 

[MrGiggles]

The coils pretty commonly fail. Chinese coils from parts stores are especially bad about it. Replace the coil, and get one with a lifetime warranty.

 

[MrsZR7]

I'm not sure where these are made, but they do have a lifetime warranty. One thing I've made sure to do with this car is to buy everything from O'Reilly, so that everything is on record there and I have no question of where I bought something if it goes bad.


Sent from my iPhone using Tapatalk

 

[The_big_dill]

Then get a replacement because your diagnostics point directly at the coils. The coils are half of the problems with these cars. If your issue persists its probably the EGR.

 

[MrsZR7]

Even if it takes 6-10 months? I know very little, but I thought it might've been an immediate cause and effect kind of thing.


Sent from my iPhone using Tapatalk

 

[mazdadude]

Then get a replacement because your diagnostics point directly at the coils. The coils are half of the problems with these cars. If your issue persists its probably the EGR.

Agreed. The coils get baked by the high engine temps and the stress of going from cold to HOT.

Sounds like you identified the bad coil. (make sure the "NEW" one you get at parts store is new and clean and not a returned one.)(braindead

 

[The_big_dill]

Even if it takes 6-10 months? I know very little, but I thought it might've been an immediate cause and effect kind of thing.


Sent from my iPhone using Tapatalk

Its hit and miss with these coils, replace them, they are free for you!

I have heard of new coils being bad.

If you live in a hot climate, its that much worse. I have original cold and am at 230000km but I live in Canada and have Mazda coils. This is what I mean by hit and miss.

 

[MrsZR7]

Yeah we've already done that and it's running fine again. I'm just worrying that there's a potentially major underlying problem since it keeps happening every few months or so.


Sent from my iPhone using Tapatalk

 

[The_big_dill]

Heat would be the main issue, but there isn't much you can do about that besides splurge on OEM coils which are designed to run in that environment.

Any other obd codes?

Does the engine overheat?

How hot does it get where you are located?

 

[MrsZR7]

Heat would be the main issue, but there isn't much you can do about that besides splurge on OEM coils which are designed to run in that environment.

Any other obd codes?

Does the engine overheat?

How hot does it get where you are located?

Nope. The engine has never overheated and there's no other codes. Whenever I've had a problem that caused the CEL to come on, it has only been misfires or the time when there was a hole in the stock air intake tube.


Sent from my iPhone using Tapatalk

 

[The_big_dill]

Do you keep track of your temperature gauge?

It sounds like you care for your car well, but you haven't had luck with coils.

If replacement of the coils fixes the problem then there shouldn't be any other underlying point of failure.

 

[MrsZR7]

Do you keep track of your temperature gauge?

It sounds like you care for your car well, but you haven't had luck with coils.

If replacement of the coils fixes the problem then there shouldn't be any other underlying point of failure.

Yes, I keep a close eye on the temperature gauge. The 2002 Ford Focus I had right before the P5 had some gremlins that I never could work out - and the #1 gremlin was cooling. It drank antifreeze like it was free beer but STILL overheated in the summer. It also went through two alternators in less than 6 months.
But since having cooling system issues with that car, I've been in the habit of keeping a close eye on the gauges of any vehicle I'm driving.
And yes, I have actually taken up maintaining my own car as a hobby. I've learned as I go along. I put cold air intake systems on both the Focus and Mazda, do all my own tune-ups, and I'd like to try doing my brakes pretty soon.


Sent from my iPhone using Tapatalk

 

[The_big_dill]

Sounds like you know what you are doing. Let us know if you have any trouble with the brake job.

 

[MrsZR7]

I really really hope these cylinder fouls weren't due to my mistakes, but it does seem straightforward enough.
Brakes will be something totally new for me. I've not attempted that myself yet. My biggest challenge will be teaching my husband to only come when called. He seems to have a little difficulty with me wanting to do my own auto maintenance. Even my dad let me do the air intake system myself - I just used his garage...and his beer.


Sent from my iPhone using Tapatalk