Engine Misfire

[mike257]

Hey guys.

More problems. Ive come to accept the pinging as a "what can i do but look for higher octane gas" anyhow the engine misfire continues, its driving me nuts. I had the plugs changed twice, now im running NGK's from my local performance shop, still nothing has changed. They also discovered a leak in the intake, which when fixed sped up the car considerably. But most importantly, when i was in stop and go traffic in Chicago and Minneapolis this summer, the car is bumbling and rumbling to no end, it just feels horrible. Im also running 7.5mm Mopar Performance wires. Any idea what this could be, chrysler cant diagnose it, neither can my speedshop, ive now been into the shop a total of 5 times on this issue.


Thanks
Mike

[Mean Green]

quote:Originally posted by mike257

Hey guys.

More problems. Ive come to accept the pinging as a "what can i do but look for higher octane gas" anyhow the engine misfire continues, its driving me nuts. I had the plugs changed twice, now im running NGK's from my local performance shop, still nothing has changed. They also discovered a leak in the intake, which when fixed sped up the car considerably. But most importantly, when i was in stop and go traffic in Chicago and Minneapolis this summer, the car is bumbling and rumbling to no end, it just feels horrible. Im also running 7.5mm Mopar Performance wires. Any idea what this could be, chrysler cant diagnose it, neither can my speedshop, ive now been into the shop a total of 5 times on this issue.


Thanks
Mike

Sounds like you may be able top go after the lemon law. I think you are already at the limit of attempts to fix it. Check out the lemon law in your stste.

[bobs turbo pt]

if you can try the lemon law, make sure you can document everything !! let us know how & what you do

[mvandale]

I'd still bet on the wires. I had a 6-month old set of Magnecor wires in 8.5 mm diameter (highly recommended here) and they started misfiring. This was after the stock wires did the same thing after 1 year of use. Tried Mopar Performance wires . . . they lasted 8 months. Each time, I replaced the plugs (first with NGK, then Champion).
I'm now using off-the-shelf NGK wires, resigned to the fact that I'm going to be replacing the plugs and wires every year. I have no idea why these cars go through wires so fast (I've even tried to use heat shielding on some of them with no better results), but all my late-model Dodge/Chryslers eat up plug wires unexplicably.

[mike257]

Hey guys,

Im from Canada, i have no idea if there is a Lemmon law thing here. But the wires were swapped in when i got the St. 1 in there and pretty much since then it has been misifiring, they never diagnosed it as that, but i guess it still could be. I guess ill get them changed and let ya know.


Mike

[littleblueGT]

I have been using the "Bosch Premimum plug wires" from Autozone for three years now and they come with heat shields and are guaranteed for life! They were the same price as the OEM plug wire set that had 3,500 olm resistance and the Bosch had only 75 olm resistance. You could pay more for wires, but why would you want to!

[crazyjoe]

If you're going through wires and plugs that quickly (which you aren't, they probably aren't bad, just they were perfect brand new), you might want to check into a new ignition coil. For the prioce of a set of magnecores you can get an aftermarket ignition coil (about 85 dollars) and see if that resolves your problem.

[quicksilverdon]

From all the PT forums I'm on and my own experience - 95% (or so) of the time the missing is plugs/wires - they should both be done at same time - a bad wire can ruin a plug & vice versa.
There are some cases of bad camshaft and crankshaft sensors - they usually trigger a CEL, but the missing often won't.

[dsouder]

quote:Originally posted by mvandale

I'd still bet on the wires. I had a 6-month old set of Magnecor wires in 8.5 mm diameter (highly recommended here) and they started misfiring. This was after the stock wires did the same thing after 1 year of use. Tried Mopar Performance wires . . . they lasted 8 months. Each time, I replaced the plugs (first with NGK, then Champion).
I'm now using off-the-shelf NGK wires, resigned to the fact that I'm going to be replacing the plugs and wires every year. I have no idea why these cars go through wires so fast (I've even tried to use heat shielding on some of them with no better results), but all my late-model Dodge/Chryslers eat up plug wires unexplicably.

[4SPEED]

could also be that a valve is not closing, a defective injector, coil breaking down...point is there could be many different causes. if the dealer doesn't seem to fix it than tell him you want to see the factory service rep the next time he comes in. generally they visit a dealer once a month. I used to be a service mgr