hey guys ive just changed my mates engine in his mazda, the engine was changed because his old 1 got a roasting and packed in. he had another v6 for a doner so we swaped them. our problem is that the new engine is cranking but not starting. any ideas where the problem lays? heres a brief bit about what is happening, there is no spark coming from the coil and no petrol to the fuel rail. ive checked the associated relays/fuses and the coil was changed along with various other parts. were really stuck if any one can help or point us in the right direction we would be greatfull. looking 4ward to some of your replys. thankz

 

What kind of Mazda is this on?

 

What MT said? ^ ^ ^
I will say though that if both engines are controlled by an ECU and you did not use the one from the donor car, that just might be you main problem right there.

 

its a 94 626 v6, should the old ecu not be ok on this model/age of mazda?

 

MT might be able to say more than I, but if they are both 94 626's using the same transmissions I would swap it out just to be sure. And if they aren't the same year, I would certainly swap them out.

 

would changing the ecu mean having to change the whole ignition also in this model as there is a coil around the key barrell?