On Going Misfire

[MercuryT]

Hi All,

As you have read before I have had and continue to have a problem with an engine misfire. Basically what happens is if I load the engine up in 2nd or 4th in manual mode it gets to about 2,750 - 3,000rpm and has this misfire like the traction control is working yet the light is not flashing. The problem only occurs in 2nd and 4th. In 3rd the car is great, no misfire, nothing!!

Ford have replaced a burnt out PCM along with a few coil packs. When the problem was still there they told me to put back the standard Ford file and surprise surprise the problem goes away, they are now saying "not our problem".

Simon & Dave @ NizPro have been extremely helpful but are at a lose as to what is the cause. I was hoping somebody might be able to shed some light on this issue.

My Processor code is one of the lucky ones that doesn't have the "Force Motor Control" for the transmisson in it and I am wondering if it has something to do with the torque limiting of the engine to prevent destruction of my auto. One of the holes in this theory is that 3rd should be worse than 2nd and it is great in 3rd!!

Simon & Dave have replaced all 6 coil packs, fitted new regapped Typhoon plugs and still no good. If I leave the car in Auto it seems better because it is able to rev through this band quicker. It still does it in 2nd, like when I turn a corner and apply about 1/2 throttle, not enough to make it kick down to 1st but enough to make it rev beyond 3,000 rpm.

Any ideas??

[geea]

I'd say that your auto is slipping in 2nd and 4th cause the band is shot and that the car is somehow confuing this with lack of traction.

Have you tried driving with traction control off and if so does it still do it.

Geea.

[MercuryT]

Hey Geea,

Traction Control on or off, it doesn't matter. The auto certainly doesn't seem to be slipping. We can get this to happen "on demand" on the dyno. NizPro checked fuel pressure as well and no problems there.

I am running out of ideas. When Ford tried to fix it they said that the "numbers" they were getting from the diagnostic tool didn't make any sense and that is why I needed to put it back to standard.

[Adam]

Is it currently standard?

[MercuryT]

No. I have put the NizPro 98 file back in it as it is a far nicer car even with the misfire. It is 100% better off boost than the standard file and I don't drive it hard but occasionally when I want to give it a squirt it misfires and that really annoys me. It is now out of warranty but Westpoint Ford know about this issue and have told me that they will look after me. I understand that if it doesn't play up at standard that their hands are tied. I am trying to get it to Simon and leave it for a few days but have been busy.

[xlnt6]

I had a similar problem, which started after the weather got colder. The symptoms are identical, except I have a manual, but the RPMs match up and it occurred under load.

Anyway it was a simple matter of plug gaps. The plugs in the car had been changed at some stage to NGK BCPR7RES gapped at 0.8mm, and I swapped them back to factory AGSP22Z11 with a 0.7mm gap (which is 0.1mm less than what most guys have) and problem gone. Now smaller spark gap is meant to cause poorer idle, but I haven't found any difference.

Now Dave and Simon, know their s..t so they probably have already tried that. I don't know what Typhoon plugs are vs XR6T plugs, but it should be pretty simple to try a slightly smaller gap. Also from my previous experiences I'm not a supporter of the colder plug in a street application, which the 7 range is, hence another reason I swapped back to the OEM plug. I'm guessing it's probably a 6 heat range plug (???), as most cars come from the factory with 5 or 6 heat range plugs. Anyway.... I digress. Give it a try !!

Cheers

Robin.

[MercuryT]

Hey Robin,

We have tried plug gap, down to as low as .05 and still no good. Simon was wondering if it was a poor earth because it has burnt out a few Coil Packs. But it is not an issue in 3rd so that also puts holes in that theory!

I have no idea what to do next! When I first got the EDIT done Dave replaced all the plugs with new OE regapped ones (I think .08) The car seemed OK for a few days but has come back and has been an ongoing issue for a few months now. The only good thing about this issue is that it was giving me problems before I got the EDIT so I know it is not a NizPro problem. Simon wants to build me a new tune slowly and see where it develops the misfire and then they can work back from there. This sounds like the only solution!!

Simon told me has never seen anything like this before which was always going to happen with my car!!!

[G6ET8U]

What a shame you're experiencing problems with your tune... at least Nizpro is willing to work with you and your car on finding a solution for why this is happening... only problem is solutions take time and that means time without your car which sucks... but atleast the you can 'drive around' the problem.

It is also good that and somewhat unheard of that Ford are also coming to the party... good luck with it.

Hope it all works out for you mate! All the best... you're in good hands with Simon.

Jack

[Mr_4.0]

What was the result of this??