Scoobler

Have a fiesta that started life as a 1.25 16v, after it threw a rod through the block we did an engine change and stuck the 1.6 16v out of a newer fez in. It has been going great for a few months now.

But it has started playing up, at first it had an intermitant missfire. Now its completely dead on two cylinders.

We have tried:

Another DIS pack.
Swopping the plug over to the DIS pack and the opposite two cylinders that worked then didn't and vice versa - so shows the DIS pack works, and its not the HT leads or spark plugs.
We have checked the signal wires back to the ECU for continuity, which it has so shows there is no break in the wire.

As far as I can see there is no ignition amplifier? So I am assuming there is a driver built into the ECU (nothing inside the box looks burnt out....)

Will any 1.6 16v ford ECU do the job, or do I have to get another CHCA one, just there seems to be a few different ECU codes?

Or is there anything else we can try?

Thanks in advance!

murdoch1.7zs

this happend to my mate zetec s fiesta. started missfiring then ended up melting 2 pistons

i think other ecu's with different codes will work ok but you will need to get the code from your key to match the ecu or it wont work at all.

i have an chca ecu in my garage aswell

SafeChav

You sure its definately lost spark on 2 cylinders and its not anything like the head gasket failed?

Scoobler

SafeChav - its defo lost its spark on two cylinders, H/G is fine, well that is no compression loss and leakage was well within tolerance, no water loss and no oil loss.

murdoch1.7zs - dont suppose you would want to sell the ECU you have in ya garage (have you got the key to match, or the chip out of it, already have the zetecs chip taped to the receiver tucked up in the dash ) ? If so what kinda price would you be after (PM if you would prefer ) ?

Thanks again

SafeChav

Which cylinders have you lost spark on, presumably it would be 2 that fire off the same coil.....

The later type ECU's do have EDIS built into them by the way.

Scoobler

Sorry should have said, yes its one coil that doesn't fire. If you swop the two signal wires over that go to the DIS pack the opposite coil stops working, and the coil that wasn't firing starts firing. Showing that both coils work, but only one signal wire is sending a signal from the ECU.

Presumably the crank sensor being a single unit (it is the crank sensor that tells the ECU where the engine in, which in turn tells the DIS when it needs to fire?) wouldn't stop the DIS working like this?

SafeChav

Right, so you need to disconnect the battery, and unplug the ECU and the plug on the coil, and do a simple continuity test on the LT wires.

Indeed the crank sensor merely tells the ECU when the engine is at 90 degrees BTDC, so theres either a wire gone open circuit or the ECU has an internal fault.

If the LT wires are all ok try another ECU, should be a simple fault to fix

Scoobler

Cheers SafeChav - have done the continuity test, tested the cable from ECU to DIS and it had continuity. Tested to ground and nothing, showing the cable hadn't broken and wasn't grounding.

Looks like a new ECU time

cheers again

SafeChav

No problem

keep us posted

murdoch1.7zs

i dont have the key with the chip in it. i just got my key reprogramed to the puma ecu.

im going to be selling the car soon so i will let you know about the ecu