I had time to think while striiping the donor of its loom....I've always assumed I'd be using the zetec ecu that came with the zetec when all's done and built. But just checking, would that be ok with the sierra cvh loom? Or would the cvh ecu be used on the zetec?

I read a lot about cvh-to-zetec being an easy upgrade, but not sure how true this is when talking about the electrics. Are most of the plugs the same?

Oh also...I don't have the keys for the zetec so if it came from an immobilised car I'm not sure if I can bypass the immobiliser on the zetec ecu? ( The engine is 1999 2.0 blacktop and from a mondeo)

Any thoughts? Ta very much!

I am afraid no keys no workie on the black top ecu. Pats can not be diy bypassed or reprogrammed. So that ecu is a paper weight.
A dealer can recode new keys. But it would need to be in the car and you would need the v5 ect and costs when I enquired ten years ago where circa £300. I e they didn't want the job.

The ecu on the sierra cfi injection is a non starter as well. It was a very basic system lashed up to get shot of the very last of the sierras. A single central injector into a re purposed carb.

Had you got the keys for the mondeo you still could not use the sierra loom. If the sierra used the eeciv it's a 60 pin ecu. The Black top mondeo is a 104 pin eecv ecu and the pins are much thinner.

The focus eecv is a 60 pin ecu but there is still not enough scope for a conversion from the sierra cfi loom.

Thanks Wasa, if anyone knew the answer it'd be you You're right the donor is EEC IV so that put's any hope out the window

So the way I see it here's my options:
• Use the CVH instead of the Zetec (Easiest option but don't want to do this if I can help it)
• Get a mk2 2.0 Mondeo ECU with keys (I have the Zetec engine loom back to where it connects with the main loom, so will have to find some way of connecting it together to the Sierra/getting the rest of the Mondeo loom?)
• Custom loom (Expensive?). Would require new ECU too I guess

Am I missing anything, is there a secret 4th option!? (please!? )

[Edited on 25/1/17 by christim]

If you have the engine loom you don't need the car loom but you would need a few odds an ends like aerial and obd2 plugs from the car. Just an ecu with keys needed.

local breaker was only asking £25 for ford ecu and keys....
you might find the same, most of them just get scrapped with the car.

Aah that's great. I've bought a new ECU with keys now, and will get hunting for the other bits needed to attach to my zetec engine loom connectors
Thanks so much for the help! Was starting to worry I'd get the build finished only to find none of it worked