Misfires

[Redfire03GT]

Ok, I've taken my car to Ford 3 times now. I have a pesky consistant misfire. Each time, they change the plugs thinking it'll fix it. I put in Autolite 764's at first, still misfired, then I tried APP764's, double platinums, still misfired. Then I tried Motorcraft platinums, still misfired. Ford has changed the plugs themselves 3 times and it still misfires. It seems to be eluding everyone who works on it.

The plugs were gapped properly. The timing is at stock. The coil packs are fine, according to Ford. None of the wiring is shot, once again, according to Ford.

The misfires only happen under heavy load/high rpms or sustained rpm's. Under very casual conditions, the car doesn't act up. But once that misfire code sets off, the car immediately becomes gutless and remains so even after the service engine light is off. The only "cure" is to reset the computer. Then, for a brief while, it's back to it's peppy self.

Ford has my car yet again, today. If the problem still isn't solved, what should I try next? I've been looking into getting a plasma booster purely for the sake of it's supposed ability to cure misfires. But, i feel that even that is merely a band-aid. I'd like to actually solve the problem not just simply make it go away by drowning it out.

Thanks for any info.

 

[allutz]

what codes are coming up???? is it random cylinder misfire(300) or a specific cylinder???(301-308)

 

[chinostang]

Does your car have trac control? My old 99 gt had a faulty sensor or something that made the trac control come on which does some cooky misfire type of thing to it. Just one among many reasons why it was a lemon.

 

[Redfire03GT]

what codes are coming up???? is it random cylinder misfire(300) or a specific cylinder???(301-308)

Both.

Cylinders 3/4 are pretty consistant as far as showing up with a misfire and I'm getting the random misfire code.

I've spoken to Ford about that several times and they insisted the coil packs are fine and it was the spark plugs at fault. Even the ones they had replaced.

After speaking with them again today, they're going to replace all my coil packs and plugs once again in the hopes that it'll finally solve the problem.

 

[ChaosStarter]

check over all of your plug wires. look for white marks on the wires. if the wires were even close to metal, the spark will try to get to ground (least resistance path) and it'll go right through that rubber.

The white marks are ozone forming on the wires. if you see some marks (double check cyls 3/4), change your wires, and get them away from metal.

 

[bdcardinal]

check over all of your plug wires. look for white marks on the wires. if the wires were even close to metal, the spark will try to get to ground (least resistance path) and it'll go right through that rubber.

The white marks are ozone forming on the wires. if you see some marks (double check cyls 3/4), change your wires, and get them away from metal.

no wires on his ride, 99+ have packs

 

[Go HoTO!]

I saw your post at MD and responded. Check out my comments. It the C&L MAF that is causing the problem!!!!! Take it off and put the stock MAF back on. Same thing happened to me in April. The C&L MAF was causing my car to run too lean and when the weather warmed up, BINGO, missfires. I took it off, and problem was solved....for good.

 

[Joeycash718]

Ok, I've taken my car to Ford 3 times now. I have a pesky consistant misfire. Each time, they change the plugs thinking it'll fix it. I put in Autolite 764's at first, still misfired, then I tried APP764's, double platinums, still misfired. Then I tried Motorcraft platinums, still misfired. Ford has changed the plugs themselves 3 times and it still misfires. It seems to be eluding everyone who works on it.

The plugs were gapped properly. The timing is at stock. The coil packs are fine, according to Ford. None of the wiring is shot, once again, according to Ford.

The misfires only happen under heavy load/high rpms or sustained rpm's. Under very casual conditions, the car doesn't act up. But once that misfire code sets off, the car immediately becomes gutless and remains so even after the service engine light is off. The only "cure" is to reset the computer. Then, for a brief while, it's back to it's peppy self.

Ford has my car yet again, today. If the problem still isn't solved, what should I try next? I've been looking into getting a plasma booster purely for the sake of it's supposed ability to cure misfires. But, i feel that even that is merely a band-aid. I'd like to actually solve the problem not just simply make it go away by drowning it out.

Thanks for any info.

im having missfires myself, i just added a cold air kit and a new tps. now my car is so fuct up its not even funny. it sounds like a popcorn maker coming down the street. 2 different mechanics cant figure the problem out

 

[Bluffing024]

im having missfires myself, i just added a cold air kit and a new tps. now my car is so fuct up its not even funny. it sounds like a popcorn maker coming down the street. 2 different mechanics cant figure the problem out

Why bring a 3 year old thread back?

 

[Joeycash718]

Why bring a 3 year old thread back?

i didnt even realize the date

 

[geoffsgt]

This is what happens when people constantly get bitched at to do searches.

 

[Bluffing024]

This is what happens when people constantly get bitched at to do searches.

Well, I guess this shows at least he did search...

 

[COramprat]

im having missfires myself, i just added a cold air kit and a new tps. now my car is so fuct up its not even funny. it sounds like a popcorn maker coming down the street. 2 different mechanics cant figure the problem out

You are getting detonation. 1st step would be to try a higher octane gasoline or at least run a major brand, if you are not already, and see if that solves it.

 

[Bluffing024]

You are getting detonation. 1st step would be to try a higher octane gasoline or at least run a major brand, if you are not already, and see if that solves it.

Thats what it sounds like he is describing, but it may be another noise if he has had it to two different mechanics and they couldn't tell it might not be detonation. But definitely get the highest grade of gas you can to be safe and see if it goes away.