Plug gap between 0.040" - 0.050" should be fine. The coils are just held in place by the bolts, 5 lb-ft is all that is needed. You didn't put the fuel filter in backwards did you? There should be an arrow on it and it should be facing towards the engine.
2006 Mustang GT misfire after tune-up, things to check?
Car has 58k, on Saturday I replaced the stock plugs with the Champion one piece. Gapped to spec, torqued to 25ft lbs. Also replaced the fuel filter. Car ran good all weekend. Tuesday morning on the way to work, about 75 miles later, I noticed a slight intermittent missfire. Mostly between 1000-2000rpm under light throttle. Still runs fine otherwise and has plenty of power. Doesn't seem to missfire under heavier throttle.
Anything in particular I should check? I thought maybe I closed one of the plug gaps putting them in but then I don't think it would run good under heavier throttle.
I did notice I snugged the coils back down with a 1/4" drive ratchet, I looked at them and I can wiggle them with my hand but I didn't want to overtighten them and chance breaking them. How tight should they be? Hopefully it's just causing a bad ground or something
Anything in particular I should check? I thought maybe I closed one of the plug gaps putting them in but then I don't think it would run good under heavier throttle.
I did notice I snugged the coils back down with a 1/4" drive ratchet, I looked at them and I can wiggle them with my hand but I didn't want to overtighten them and chance breaking them. How tight should they be? Hopefully it's just causing a bad ground or something
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Yep the fuel filter was marked inlet so that's good. I didn't think the coils needed to be super tight but I thought it was odd I could wiggle them. I didn't try before removing them though so I don't know if you could wiggle them before...
You might just have a little corrosion on the coils. You clean them with a wire brush. Then apply some di-electric grease. Just to be safe I would check the plug gap again too. I would run some fuel injector cleaner through the system. See if that clears it up.Yep the fuel filter was marked inlet so that's good. I didn't think the coils needed to be super tight but I thought it was odd I could wiggle them. I didn't try before removing them though so I don't know if you could wiggle them before...
Ok. The coils didn't look corroded or anything but I'll pull em out this weekend and go over everything once more. Odd that it ran good for the first few days, maybe something is just coming loose.
Electronics can be finicky at times. If there was as a problematic issue you would get a CEL. I presume you are not.Ok. The coils didn't look corroded or anything but I'll pull em out this weekend and go over everything once more. Odd that it ran good for the first few days, maybe something is just coming loose.
Did you use an actual sparkplug socket with the neoprene insert and make sure not to put any lateral force on the plug when tightening it?
If you are not careful it is very easy to crack the porcelain insolator on any sparkplug and that would cause the symptom you are having.
If you are not careful it is very easy to crack the porcelain insolator on any sparkplug and that would cause the symptom you are having.
yeah, more than likely one of the plugs is loose or the connector...
Nope no light. I think the gap I used was .045 so that should be fine. I'll check it out again and put dielectric grease on the boots. And I did use a plug socket. They are so easy to get to I don't think I damaged any putting them in. I even torqued them to spec 25ft lbs
I have fixed two Roushcharged Mustangs that had mismade sparkplugs. Both cars had a misfire on cold start up and would run ok after a few minutes. It turned out the center electrode wasn't exposed enough thru the ceramic. If you look closely at the center electrode it should have two steps. The thinnest step should be above the ceramic by a couple of millemeters. This may not be you problem, just something to look for. These plugs were -1 heat range Autolites.
Well it rained hard last night. This morning the car was running really rough and the CEL was flashing. After a few minutes the car warmed up and was running fine and the light went back out.
Can you read the CEL? I just replaced my plugs last night and it runs like a top now. I used the Autolite HT1's though.Well it rained hard last night. This morning the car was running really rough and the CEL was flashing. After a few minutes the car warmed up and was running fine and the light went back out.
No I don't have a tool to read it, and I'm pretty far from home until sunday. The best I can do here is pull the coils, put some dielectric grease on them and make sure they're on right. Or take it to a local shop. Even home I don't have a code scanner but the light is out now.
You could always take it by an Autozone or the like. They read codes for free. It should be stored in history even if it isn't current.No I don't have a tool to read it, and I'm pretty far from home until sunday. The best I can do here is pull the coils, put some dielectric grease on them and make sure they're on right. Or take it to a local shop. Even home I don't have a code scanner but the light is out now.
I stopped at a local Advance Auto after work. They checked and there were no codes. It ran fine all the way home. Go figure...
Still acts up once in a while. No rhym or reason. I drove it in the pouring rain fine, but today it was acting up all the way too and from work. I think when the change allows I'm going to have the dealer reflash it, then reflash it with a predator. I think the car was tuned before but I don't have a tuner so I think I need to start over.
Had the same problem this morning again. No rain last night. Car ran rough and idled around 500rpm instead of 750. CEL was flashing. After about two minutes by the time I got off my street the light went back out and it was running smooth like someone hit a switch. It still sputtered a little once in a while on the way to work, but not bad enough to diagnose or get a code from.Well it rained hard last night. This morning the car was running really rough and the CEL was flashing. After a few minutes the car warmed up and was running fine and the light went back out.
I have fixed two Roushcharged Mustangs that had mismade sparkplugs. Both cars had a misfire on cold start up and would run ok after a few minutes. It turned out the center electrode wasn't exposed enough thru the ceramic. If you look closely at the center electrode it should have two steps. The thinnest step should be above the ceramic by a couple of millemeters. This may not be you problem, just something to look for. These plugs were -1 heat range Autolites.
Well youere darn close. I pulled the Champions out today and I notice the one rattled. The ceramic tip must have been cracked inside the barrel. The electrode was the only thing keeping the tip of ceramic from falling right off. Napa gave me another no problem and I should be good to go now. Thanks again everyone!
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