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cosworth on link g4 plus need help

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Posting this to see if anyone comes up with something that I might have missed.

So my fiesta Cosworth has been running perfect!! Started it to move it out the way walked back over to it 2 minutes later and it was running like a bag of S***! Running on a link monsoon ecu cop conversion. Bosch ev14 injectors bought brand new only a few months ago. Went to move it and it cut out. Tried to restart it and tries to fire but backfires. Pulled the plugs all fouled up! New plugs fouled them straight away. Tested coils and injectors through link software all clicking ok. new genuine phase and crank sensors fitted a few months ago and both gapped fine. Re checked and still ok. also has new iat and ect sensors fitted. Vacuum pipe to map sensor that’s built into the ecu is fine. Cannot find any other leaks have smoke tested intake system. Fuel pressure is good as I suspect with how rich it is! Tps sensor is working fine as checked on live data. Cannot see anything untoward. Now I cannot get it to start at all. Just turns over. Done a compression test for good measure 150psi on all 4 cylinders. checked timing and spot on. found an earth wire that was disconnected on the block so re connected it. removed plugs and left out to completely dry out. got it to start but runs awful and will not idle. i logged it and have attached the logs. don't know where to go from here can anyone see anything that i am missing ? thanks

Attached Files

You say it "has been running perfect" - was that for some time or just on this start-up on a fresh tune/build?

Are you sure you haven't knocked something or accidentally disconnected anything - unless you made a change to the 'tune', just making changes there in the hope of fixing the problem will just make things worse if it's a sensor or power/ground issue?

I'd start with a check of all the comnnectors for sensors/senders in case one wasn't quite in place and has disconnected itself or has an intermittent contact, then go over the various hoses and check for a disconnected, cracked or split hose - there's a good chance it's the MAP line, if used.

Did you actually check the fuel pressure or just assume it was correct and not too high - such as a blocked fuel return or faulty regulator could cause?

Is it on closed loop - if there was a misfire it would show a lean condition and the ECU may be adding fuel to "correct' that and, as the misfire gets worse from being too rich it will continue to add fuel as the unused oxygen will be showing an increasingly "lean"condition?

Hi Gord. when I say its been running perfectly I had the car mapped around 6 months ago and have been driving the car without any issues. nothing has been touched or knocked. the car was reversed back left to idle for 2 minutes and when I come back to it I had this issue.

I have only plugged into the car to log whats happening.

I have been through every connector and all pins are located and all plugs connected ok. I have tested the fuel pressure with a manual gauge and also have a sensor in the regulator that is giving me the same reading as the gauge of 3 bar pressure.

as I said above I have carried out a smoke test on the inlet system. and no leaks. I have also replaced the pipe to the map sensor to eliminate this but no luck.

it is on closed loop but can't even get it running well or long enough for the can lambda to start reading. I have however used my mot lane emissions tester and it is rich.


I don't know a thing about Fiesta, but if you have access to an oscilloscope, I would check the injectors signal to ensure it's okay. Maybe some signals are shorted together or grounded and it's injecting additional unwanted fuel.

It's really weird that it just started happening like that. With a carbie I'd also be checking nothing was sucked up to block the filter, but that's unlikely to be an issue for you. All in all, you've covered everything that comes to mind

There may still be a fouled 'plug, or two, that are mis-firing and letting oxygen pass to the lambda?

Have you pulled the spark plugs and cranked it over with the injectors disconnected to get rid of excess fuel in the posts and cylinders?

Then when you're sure the excess has been pumped out, fit new spark plugs and try again.

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