Long story short I had a obd0 b16 and now have a obd1 lsvtec. I have a Monotek conversion harness, obd1 ecu/dizzy and put in a Gm 3 bar map sensor. With the obd0 ecu in, the pump primes normally. When i hook up the ond1 ecu (p30), I have no fuel pump. Is there something that the obd1 ecu might be looking for (electronic wise) that the obd0 ecu does not need in order to prime the pump? Another strange thing I noticed is that my 5 volt coming from the radio is also staying on with the obd1 ecu. If you have any ideas please let me know because i need this thing out of the garage!

 

bad jumper

 

Anyone else have any idea? I made sure the wires on the conversion harness for the fuel pump are in the correct order.

 

i actually had a bad ground when this happened. check the thermostat ground seems a little rediculous but hey....

 

I was just double checking my conversion harness and found that the wire for crank position sensor was broken. would this affect the fuel pump? I think it may just be the harness because the fuel pump primes without the harness and using the obd0 ecu.

 

Thanks for the help. I am ordering a Boomslang harness and hope it fixed the electrical issue.

 

It wouldn't affect pump priming, but my guess is if there's one issue, there may easily be more. I've used boomslang harnesses before, they're very nice. They're not cheap like ebay CDM crap, but definately worth it.

 

Put in the boomslang harness and still have the same issue. Double checked my grounds. With the obd0 pr3 ecu, the pump primes as it should. One harness and obd1 p72 are plugged in, the pump will not prime. Im pretty sure it has to be the ecu? All wires were checked and it seems like the ecu is the only thing that could cause all these issues?

 

It was the ecu. Did not have any other probs with the ecu. It just would not prime the pump. I am having it checked out by the kid who chipped it.

 

The problem is most likely the ECU/ECM, either the fuel pump relay control, [ground out from ECU/ECM] is not working or one or both of the 12V+ input from injector realy to ECU/ECM is not working, either way the fuel pump would not work. 94

 

I am sure it is something inside the ecu. Like I said, i swapped in another ecu and it worked fine. I did a visual inspection, but am sending to john from j-k tuning to diagnose because he has an ecu simulator. I am kinda pissed i went through my entire wiring harness and even ordered another jumper and found out it was the ecu...