Thread: Weird injector problem.

So far I have not had any problems with the injectors in the G20. But today was a weird one. I drove the car all day, and it showed no signs of problems. After leaving a mcdonalds, the car idles a little funny, so I give it some gas, still doesn't improve, I pop the hood, fuel pressure is a little low (20psi range), so I raise it up, and its still not doing anything. Eventually car shuts off, and will not start again.

I check every possible scenario in the parking lot, fuses, spark plugs, fuel pump, hell I even pulled off the valve cover to make sure I didn't pop a rocker off or something. So I pull the rail out, and crank it, and no fuel comes out. Again, I check to see if the fuel pump is good, if theres pressure in the lines. All that checks out.

So basically all 4 injectors are dead. I checked the harness, each injector plug has power. Real bizzare. Eventually I use a set of 370s, and I had another injector harness and changed my ecu for that setup to get home.

The injectors are 50lb MSD style top feed injectors, and they all died at the same time. I'll pull them out of the rail tomorrow and inspect them, but I just thought it was real weird for all 4 to go bad at once. Anyone ever experience this?

I'd find it extremely unusual that 4 good injectors fail at the same time. I'd probably start looking for something that could affect them all simultaneously. I would look at my fuel filter to make sure it hadn't broken down, possibly look at your resistor box to see if it failed, something like that. That's weird man. Sorry I don't have anything else to offer...

SO after installing the 370's the car ran fine? It is very strange that all 4 injectors would go bad at once, the fact that you had low fuel pressure also left me scratching my head.

Is it possible the engine management went awry?

Fuel filter is no more than a month old. And these are 12ohm injectors so they don't need resistors.



Car runs ok with 370s. Its a 4 bar program, and I was only running it at 3 bar. I also had a stock ecu I put in just to see if the ecu could be a problem. It still didn't work.

Serban,
Check the Power Transistor. Ive seen this happen when the Power Transistor died.
Heres how to test it with your DVM:

Power Transistor Test
. ----|||----
( A || B || C )
\-----------/
- Disconnect power transistor harness connector.
- Check power transistor continuity between terminals as follows:

Pos (+) . Neg (-) . Resistance . . . . Result
. A . . . . . B . . . . . Infinite . . . . . . Good
. A . . . . . C . . . . . Infinite . . . . . . Good
. B . . . . . A . . . . Not Infinite or 0 . Good
. B . . . . . C . . . . Not Infinite or 0 . Good
. C . . . . . A . . . . Not Infinite or 0 . Good
. C . . . . . B . . . . Not Infinite or 0 . Good

Pos (+) . Neg (-) . Resistance . . . . . Result
. A . . . . . B . . . . Not Infinite or 0 . No Good
. A . . . . . C . . . . Not Infinite or 0 . No Good
. B . . . . . C . . . . Infinite or 0 . . . . No Good
. C . . . . . A . . . . Infinite or 0 . . . . No Good
. C . . . . . B . . . . Infinite or 0 . . . . No Good

If any of the above tests show "No Good", replace.

The car is actually obd2, it does not have that power transistor. But the car ran once I put in 370s.

Also, I pulled out one injector and put power up to it, it does click on when its got power, so they may be ok...

Okay..
If the injectors are firing with power, then your problem is definately on the power side. In OBD2, do you have a Camshaft position sensor? In the ODB1 cars, its inside the drizzy and we test it by removing the dizzy and turning it slowly to hear each injector click.

Its pretty frustrating...I do have another harness I can try, maybe something screwed up with that one, who knows.

Serban, let me know how I can help, I have the full ODBII harness I just recently removed from the G20 if you want to swap that to test,

JCC

Maybe I missunderstood, when you changed the injectors to get it home did you change the ecu also?