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Engine Swapped, Now Won't Start

Carreg
Carreg
in Technical Knowledge

Featured Replies

Hi,

I've just swopped the engine in my 1996 diesel Ford Mondeo but I can't get the new one to start. I'm wondering if it's a computer problem? The ignition will work as far as turning the lights and electrics on, but nothing happens when I turn the key the final bit to start it. However, the starter motor works fine when I short it with a screwdriver, so it's not the motor itself. Also, I've tried to bleed the fuel system, but nothing seems to be coming through when I pump it.

I'm not a mechanic but usually can deal with these things. However, I've always worked on older cars than this so I am new to the issues of computers in cars.

Please help!

  • Quote


    Sounds like an immobiliser problem. You could try using the ECU and keys from the car the engine came out of

  • Quote
    • Author

    Thanks for that. Unfortunately, we haven't got the ECU and keys for the new engine so I just left on the old ECU and so am using the old keys. Does the ECU code to the old engine in some way? How do we get one to code to the new engine?

  • Quote

    I think that the immobiliser is built in to the injector pump and that is coded to the ECU, you could try using the pump off the old engine, and see what happens.

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    • Like 1
    • Author

    I've got a bit more information now - it's giving a PATS Code 31 reading. Does that fit with it being the immobilizer? I'm reaching the end of my tether with the thing now and not sure I can face messing round the pump unless there's a good chance of that working! Thanks for the help.

  • Quote
    • Author

    An update for anyone interested - we swapped the injector pump back to the old one and that did indeed fix that problem! Thank you to jay1981 - your help made all the difference.

  • Quote

    An update for anyone interested - we swapped the injector pump back to the old one and that did indeed fix that problem! Thank you to jay1981 - your help made all the difference.

    Glad to be of assistance mate!

  • Quote

    The PATS is Fords own immobilser, which is coded through to the injector pump. As said above you either use the original keys, ECU and pump or change them all to the new one.

  • Quote

    Glad to be of assistance mate!

    hi mate i have the same problem with a 2000 fiesta but i cant get hold of the car that i took the engine out of what other solutions are there many thanks

  • Quote

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