in the finishing stages of my TPI swap on my blazer and I actually had it running last week. But now not so much.

some reason I"m not getting fuel. pump primes, and I've got pressured fuel at the fitting to the fuel rails but not getting much on the return side. I put a volt meter to the injector plug but it's not getting any kind of voltage when I crank it.. I thought this was kind of weird I can spray starting stuff in the TB and it will start and run until that burns off.


injectors ohmed out at like 22 or so ohms


ecm is running the prominator and I"ve loaded a bin file. Don't remember off hand which one exactly. But it was running like 2 weeks ago which is why I'm lost on why all of a sudden I'm
getting nothing.

I don't have a fuel pressure gauge on yet, having trouble finding one locally

 

You should be getting power to the injs from a fused circuit.

You're measuring from one of the inj plug terminals to a good ground right? (as opposed to measuring across the 2 inj plug terminals)

In my case, I get inj power thru a toggle switch connected to the batt. I also have two 10 amp fuses inline. One fuse for each bank.

When the ECM wants the injs to fire, it gives them a ground.

Follow the inj wiring back into the car/truck (on the wiring harnesses I've seen, the inj wires are always twisted together). At some point near the ECM, the inj wires will split off. Ground wires going into the ECM and power wires going to the cars elec system somewhere. Use your voltmeter and find where you are losing power.

 

The typical resistance for a high impendance injector is 12-16 ohms; drawing 1 to 3/4 amp respectively. 22 ohms (1/2 amp) may not be enough current to allow the injector to open properly, or not at all. The battery needs to be properly charged, the ECM does compensate for low voltage, if that's part of your problem, I'd fix that ASAP.

You need a NOID light to test for the injector pulse; A voltmeter across the injector voltage pin and ground to test for supply voltage as was mentioned in a previous reply.

 

alright thanks guys, yea I was checking for voltage across the two injector pins in the plug. so I guess I had that wrong.

the ohm on the injector was just with my digital meter so..........