Well I finally figured something out. The CEL finally came on and I got the code scanned at AutoZone. The code read "cylinder 3 misfire. I unplugged the coil from cylinder 3 and drove around. It felt very much like it does when it misses. I did the same with the fuel injector with similar results. However, when I plugged the fuel injector back in, the engine lope went away instantly but when I plugged the COP back in it took a good 20 seconds for the lope to go away. This really makes me think that its a bad coil. At this point I'm trying to decide if I should just buy one coil from AutoZone or spring for all 8 for $150 off of ebay. Any suggestions???
Power Loss
- Thread starter Metalli485
- Start date
Alright I'm finally getting somewhere. I measured the resistance across the primary coil terminals (for cylinder 3) and it measured 1.3 ohms. According to my trusty Haynes manual it should be close to 0.55 so I'm pretty sure the coil is toast. I went up to autozone and bought a new coil for $45. When I went to install it I was pretty disappointed. The plastic housing does not have an eye hole to bolt the coil down and the boot is about a half inch too long. AutoZone parts FTL. For now, I temporarily secured it into place and went for a test drive. It made a big different because my car does not misfire at all under a moderate load. However, if I put it in 3rd or 4th gear while going about 15 mph and give it alot of gas, it starts missing pretty bad. At this point I'm going to order all 8 coils from that guy off ebay and replace everything (especially since that AutoZone coil doesn't fit right and can't be secured down properly. Does it sound like I'm on the right track at this point? I'm 100% sure that replacing that COP made things much better but I've got to have some other coils going out.
It is time to replace the plugs. If you haven't done so on one of these engines, proceed with caution. Not following the proper procedure can lead to stripped threads in the head which will be EXPEN$IVE to repair.
Only remove the plugs when the engine is dead cold. You stand a MUCH less chance of pulling the threads when the engine is cold.
Remove the COPS and blow out all foreign matter around the plugs in the plug wells with compressed air.
Use the correct motorcraft plugs. They are available at Autozone for about half what the Ford house charges for them.
Gap them correctly and apply an EXTREMELY light coat of copper based anti-sieze compound on the THREADS ONLY, don't let any of it get on the end of the plug. You can get copper based anti-sieze at most any auto parts. If can't get copper based anti-sieze, then don't use any anti-sieze compound at all.
USING A TORQUE WRENCH, tighten the plugs to 13 foot pounds.
Use a little dielectric compound in the COP boot. Ask for "tune up grease" at the auto parts store.
I will bet good money that replacing the plugs will solve your problem. It won't hurt to do a resistance test on the COPS while you have them out.
Good luck,
Only remove the plugs when the engine is dead cold. You stand a MUCH less chance of pulling the threads when the engine is cold.
Remove the COPS and blow out all foreign matter around the plugs in the plug wells with compressed air.
Use the correct motorcraft plugs. They are available at Autozone for about half what the Ford house charges for them.
Gap them correctly and apply an EXTREMELY light coat of copper based anti-sieze compound on the THREADS ONLY, don't let any of it get on the end of the plug. You can get copper based anti-sieze at most any auto parts. If can't get copper based anti-sieze, then don't use any anti-sieze compound at all.
USING A TORQUE WRENCH, tighten the plugs to 13 foot pounds.
Use a little dielectric compound in the COP boot. Ask for "tune up grease" at the auto parts store.
I will bet good money that replacing the plugs will solve your problem. It won't hurt to do a resistance test on the COPS while you have them out.
Good luck,
I've been considering replacing my spark plugs but they only have 30K miles on em and they're about 2 years old. Is it still possible that they're going out on me? I've been trying to stay away from messing with them because of spark plug blow out issues, but my dad has an assortment of torque wrenches so I know that I can do the job right if necessary. Also, I've got some serious dirt and grime at the top of the spark plug wells which gets knocked into the wells whenever I mess with the COPs. I was thinking about blowing off what I can with compressed air and then spraying some simple green on whats left and then blowing that off with compressed air (while holding a towel close to catch all the flying liquid). Anyone have a better idea for getting all the gunk off?
the98stang
Active Member
Definetly replace the spark plugs. If they are copper, they will only last 12k miles anyway.
Definetly replace all the COP's and boots. If THAT doesn't fix the problem, fill it up with different gas. Is there cheap gas in it now? What octane?
SOME mustangs actually ping and get detonation with 87 oct gas. Every car is different. So maybe it's the gas...
Right now it has 89 octane Exxon gas. I always use midgrade because it seems to always have a slight ping with 87 octane with any brand of gas. It could be possible though that I got some crappy gas and I'll find out when my next fill up comes around. I've always wondered why it pings with 87 octane. Sometimes it even pings with 89 ocatne if its cheap gas. The car doesn't have a tune and everything is stock. Is thing I can do to possibly stop the pinging aside from spark plugs?
the98stang
Active Member
Change the plugs and COP's then report back.
Be SURE to torque the plugs to 13 lbs with VERY little anti-seize. Do it when the engine is stone cold!
Rickey_Bobby
New Member
Try not to drive too long with that misfire. I now have low compression on the cylinders that were missing. Best guess is the fuel washed the oil off the cyl walls and damaged the piston rings.
Do get new plugs. Regular copper ones work great and a whole set is $9.
Make sure the plug well is clean enough to eat off of. NO MOISTURE AT ALL!
Good luck with the new coils.
Do get new plugs. Regular copper ones work great and a whole set is $9.
Make sure the plug well is clean enough to eat off of. NO MOISTURE AT ALL!
Good luck with the new coils.
I was wondering if driving a car with a misfire could damage something. I haven't driven too much and when I did drive it, I went easy on the gas so it didn't start missing. The COPs that I ordered off eBay were shipped today. I should have them by the end of the week. I also plan on putting in new spark plugs. According to the motorcraft website, I can use AWSF32P (Platinum), SP493 (Platinum), or SP413 (Nickel) spark plugs. I think I'm going to go with the SP413 spark plugs but I'm not sure. Any suggestions?
Rickey_Bobby
New Member
use just plane copper plugs. They work just as good, and no chance of the platnium tip coming off and killing your motor. (happened to my eclipse) They're cheap too. The only other plug I would reccomend would be the iridium (sp?) ones, very fine tip, very powerful spark. They suck on power adder cars though. And cost 3-4 times more than copper.
Ok, I finally fixed my problem. I replaced all 8 COPs with brand new Motorcraft replacements. My power loss problem went away, however I don't think that the COPs were going bad in the first place. I think the real problem was the rubber boot for the COP on cylinder #3. All of the spark plugs and spark plug wells looked nice and shiny except the #3 cylinder spark plug and well. It had brownish crud all over the spark plug and bottom of the well. I suspect that the bad rubber boot was allowing the coil to spark somewhere other than where it’s supposed to which cause all of the brown stuff to form. I cleaned most of it off but its still there to some extent. Anyhow, I'll probably replace my spark plugs ASAP even though my problem went away. The moral of the story here is that the boots on your COPs are just as important as the coil itself. Most of mine had cracks forming on the bottom and my car only has 60K miles (but its 7 years old). Has anyone ever seen a redish brownish coating on the spark plug and it's well?
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