Fiesta Zetec 1.25 (97) running problems

A cheap FCR is probably the easiest way to diagnose it. Assuming it's not an air leak.

Sounds like the Cat has collapsed / exhaust is blocked.

Tim..

Cat is ok.

No air leaks.

Everything on the car is the same as it was before the engine change. Engine was changed in one day, and i drove the car to the garage prior. Every thing was fine, apart from the bottom end knock, which was the reason for the engine change.

So this leads me to think that it's an electrical problem. ALL conectors have been split and re-connected to check for security. As I said before all mechanical parts have been retained from the old engine. The battery was disconnected throught the work. Has this effected the ECU? does it need to re- learn? There were only two sensors not retained and they were the crank position sensor and the coolant temp sensor. Could a faulty CTS cause my simptoms? the read out in the car seems to be working!

Cheers guys.

A Faulty CTS or wiring thereof would not cause your problems.

If you are sure the exhaust is ok, and there are no air leaks, disconnect the AMM plug and go for a drive. If 90% of the power is there, replace the AMM.

Otherwise, its time for the FCR and start looking at live data.

Tim..

Ok will try that when i get of the rig.

Thanks Tim.

I did try a drive with no intake ducting on but it would not even pull away, just huge Kangaroos and then stall. Would doing that achieve the same result as disconnecting the AMM?

No.

Tim..

have you checked the cam timing? I wasted hours on an underperforming engine once and eventually found that it was one tooth out on the cam chain.

Yes,

I fitted a new belt when the engine was out.

Cheers

In message , Mrcheerful writes

Its definitely worth checking on these engines as the crank pulley isn't keyed to the crank and its easy to lose the timing when doing up the pulley retaining bolt.

then I would definitely recheck that it is correct.

Its definitely correct.

Cheers guys

MAF sensor working OK?

Tony