Misfiring, even after changing plugs???
I’ve been having a misfiring problem with my 2001 Escape 3.0 V6 and I’m wondering if anyone else has had any similar problems?
When the problem first started to occur it would typically be on a damp day, after the truck had been sitting for a couple of days. I figured the ignition system was getting wet, causing one of the plugs to short out. The engine service light would start to flash when this happened and then stay on solid as the problem started to self correct. If you drove the truck for a short time, it would (I assume) dry out and the problem would go away. After a couple of trouble free days, the engine service light would go out. This would happen about once a month for a few months.
Last week, with the start of the snow melt, the truck once again began running sporadically. Unlike all the other times that this has happen, the weather has not cleared up and neither has the problem. If fact, it got worse. Rather then dropping the usual one cylinder now and then, it has started to effect more then one at a time and shows little sign of letting up. I decided it was time to get off my *** and fix the problem, so I set out to change the old plugs and wires. I figured out the truck has no wires and employs a Coil Over Plug (COP) type ignition, so I decided to simply changed the spark plugs.
When selecting a replacement plug I decided to go with a high quality name brand plug, due to the amount of effort required to get at the back three. I ended up deciding on the new Bosch Platinum +4. I took everything apart last night and installed the new plugs. During reassemble I inspected each coil closely and noticed four of them had small cracks on the top portion. (see Pic1 and Pic2). Not having replacement coils on hand, I decided to try and fix them by covering the top portion of each one (including the two without cracks) with a thick layer of silicon. (see Pic3). Not knowing if this would work or not, I put the two without cracks and the one with the smallest crack on the back three cylinders. This would allow me to test it and if needed, replace the worst ones (in the front) without taking the intake off again.
In the interest of not making this post any longer, let’s just say the problem is still present. It’s nowhere near as bad, but at low RPMs it is still dropping a cylinder. Anything over 2000 RPMs, it runs fine, and fires on all six. I had the battery disconnected while I was working on it so the computer would clear. During my test drive last night, I did trip a code on the computer.
Does anyone know how to pull the codes on this Escape? Usually you can jumper a couple of terminals and it will flash the codes out using the service engine light.
Does anyone have a listing of the codes and what they mean?
Anyone have any other ideas for a possible root cause?
Obviously the coil cracks are still a very likely cause, but I don’t want to go out and blow a tone of money on six new ones if the problem is something entirely different. If no one has any other ideas, what I will likely do is buy one new coil. Then I’ll swap it in and out of the front three cylinders to see if I can pinpoint which one is causing the problem. Naturally this will only work if it’s one cylinder which is consistently causing the problem and if it’s in fact one of the front ones.
I’d love to hear from anyone whose had a similar experienced, or whose got some idea about other areas to test. Like throttle position sensor (doubtful it’s the cause, but just an idea). Anyone know if it can be tested and or what the specs are?
Thanks,
Bruce