under dash short in fuel pump
 

Since I am not the original owner of my v8miata, how do most wire the electric fuel pump under the dash.

My pump comes on when the key is in the 2nd position just before you crank the car. There seems to be a wire that when moved back and forth will cause the electric pump to go off.

It seems to be a fuse=able link. My question is how should the pump be wired? I am not an electrical wiz but can follow instructions. Can anyone help?
Thanks in advance.

When I wired up mine, I eliminated all of the Mazda stuff from the system, & wired the fuel pump as it was in a Mustang. I upgraded the wire gauge to accommodate the larger fuel pump & installed a Ford fuel pump relay & inertia switch. This makes it easier to diagnose a problem if one occurs. The problem that you are having seems to be related to the "jumper wire" that is used on the Monster Miata conversion. I had read about people having issues with that thus the reason I eliminated it.

I’m not really clear on what your problem is. Does it run sometimes but sometimes not or will it not start at all? Sounds like you have power to the pump in run but do you in start? Also you don't say what year your Miata is or what your swap is – Ford, GM or ?

Your wiring could have been done or redone several different ways so you are probably going to have to just open things up and follow the wires. Do you have the wiring manual for your conversion? Martians is very clear on how it is to be wired so if you have a Ford I would start with that. If you have a GM from Flyin Miata not so much as they expect you to use their harness.

You should also have the factry Miata book for your year car because it could very well be wired that way. I just used the existing Mazda wiring in mine. A lot of turbo guys run the same 255 gph pump that V8s run and they never change any wiring so I didn’t see the need to either. Anyway the factory Miata has a fuel pump relay under the dash by the steering column that is controlled by the engine computer. Hot for the pump comes from the main relay under the hood which runs lots of other stuff too.

More detail on what you have, history of the car and the problem would be helpful.

I think he has a Ford because he contemplated a swap from T5 to C4 in a previous thread. Do your homework, Jim. LOL!!

Thank you for the info. I did find the fuel pump relay under the dash and there was a wire that had become pinched. When it was moved ever so slightly it would cause the fuel pump go off and the car shut down. Just replace the bad wire and now works great.

Thanks for the professional help.