Johndcosworth

Hello all looking for a bit of help. My 3 door cosworth keeps hitting flat spot at 5000revs. Starts spluttering and braking down. If I keep foot to the floor it will drive past it and pull away again. It's a new build whit t4 turbo and gray injectors and msd chip.

cossynut2

Sounds like you need to take it up to MSD and get them to live map it, they will find out what the problem is for sure.

Johndcosworth

Ya it would be the right thing to do but I'm in Ireland and by the time iv boat and place to stay it proble wouldn't be far off the price of a omex Ecu. It's wat I have on my race car and some job on it.

cossynut2

Sorry did not notice where you live. Are there not any Rolling Road places with guys who know their Cosworths in Northern Ireland ?

Johndcosworth

Ya loads of rolling roads but no one can live map the. I half thinking of going omex. I'm after pulling dash out of it again to cheek all the whireing. Tryed a new Ecu and all. Might try the loom tomorrow.

cossynut2

If you have tried a different ECU and it didnt make any difference I think you can rule it out, so fitting an Omex one probably will not fix the problem. I have had a new, modern specc engine wiring loom put in mine as the old looms do wear out, plus wasted spark ignition.

Johndcosworth

I had to use the chip out of the other Ecu. Just tryed friends Ecu and flying it. So it's the chip. I half to get onto msd to c if they can do anything for me as chip over a year old.

cossynut2

Glad to hear you have found the problem. The guys at MSD are good and they should be able to sort out the chip.

Johndcosworth

Ya just tryed my Ecu in my friend car and very same thing. Iv changed some amount of parts to find the prob. Thank for the a advice. I don't know is it just a faulty chip or is it something that happened it. Because when I got it first day it had to go back to them as car wouldn't even run or no spark.

Jan300

What afr value when start spluttering and braking down?

Johndcosworth

What is afr valve for.

Jan300

If using wide band lamda then you can read afr.Its a must to chekc when change injectors and chip.Its mean set up fuel.