Hi all. Does anyone have an ME221 ecu with loom for the st170. I cant afford the £800 for a new one.. ANYTHING in the way of an ecu would do provided it handles VVT. If you have anything reasonably priced then please let me know. I will not waste your time. I am in Southampton.

Big Wasa has been super helpful with the OEM unit, but, I am not getting it right. I understand all the principles but its a complex loom and the wiring diagrams on the net are difficult to follow. Im about 70% there but have hit a brick wall. Im now starting again for the third time!!!! Give me anything mechanical and I will sort it out no matter how complex it is, but electronics and I do not get along well :-[

No, don't give up.

I'm in the same boat and am now starting to see the light at the end of the tunnel. I have immobiliser working, fuel pump working, a spark. Just need to connect fuel lines up and see if she starts. I am a total novice from electrics point of view so if I can do it so can you. I got frustrated trying to work with the focus loom intact and ended up cutting all the connectors I needed off the focus loom and started soldering from there. I ditched the focus fuse / relay box and got some replacement items off eBay to suit my needs.

Thanks for that. I have done pretty much what you have but am using small crimps. Its the pats thats messing things up. Had it working perfectly with the pump etc, not its got a battery drain and the alternator is getting too hot without the engine running. Why? Goodness only knows. Thanks again mate.

I tried to get pats to work on its own as in big wasas video and couldn't for some reason, led just kept flashing. When I powered up the power hold relay it deactivated fine.

Hi.
What and where is the power hold relay? Is it to do with the fuel black box that connects to the pump? That may well be my problem.

The power hold relay supplies power to the full engine where required. It supplies +12v to maf, vvt, solenoid, idle control valve etc etc and the power hold relay output will feed into the fuel pump relay input. The fuel pump relay output will feed to the fuel pump inertia switch (black box with red button).

As above its just a big heavy duty power switch to save the contacts in the ignition switch.

If you where using s 25a rocker/toggle switch the phr could be made redundant.

Ok. Where would I place it in the loom?

Not quite ST170 but I used big-wasa guide for a blacktop. I just traced the pins from the ecu plug he had labeled and then down to the 42 pin plug on the loom which I then spliced into my car loom for power, fuel pump etc.

This is a guide I produced for the standard blacktop which may be of some help too.
http://www.martinsfurybuild.co.uk/downloads/zetec-ecu-wiring.pdf

Thanks so much for that. You guys are really helpfull.
Your Fury looks great!
Well done.

If you have any specific questions let me know as I have a running st170 on original Ecu (based on big wassa’s guide)in the garage that I can access.

Thanks very much.