DIYPNP MX5 fuel pump issues
 

Hello,
So built a diypnp for my 1991 Mazda mx5. I put a base tune on it and tried to start it without removing the ST SIG fuse and cranked it for maybe 1 min in short bursts.
Read up about it and realised my mistake.
Have since got back to working on the car and changed afew things and then it managed to fire up once with the ecu with the ST SIG fuse out.
Without touching anything I havent managed to get it to start again. It has Spark and the injectors are firing as I test with a noid light.
The fuel pump isnt priming and I have read everywhere that this is because of the ST SIG fuse blowing the driver. But if it managed to start and run since should I be safe that my driver is fine and its something else or can they be partially fried and work intermitantly?

I could jump fuel pump to 2O and jump the wires on the MAF connector but id rather get it running correctly if I could.

Thanks!

Well im going to assume it was running off fuel line preasure from stock ecu somehow as it runs fine now as soon as I jumped fuel pump to 4O (not 2O as I noted earlier)

Guess I did blow that piece running with ST SIG fuse in.

this is correctly...


you blew the high side driver inside your DIYPNP and it will never work in the configuration you have it.