1998 regal 2.8 injector problem

Mistaken Identity....1988 model not a 1998 sorry

Car ran fine , failed to crank @ McDonalds a couple hours later it cranked and drove home normally. Replaced fuel filter, black crap came out. checked fuel pressure 39-40 PSI, replaced fuel pump, now 43 PSI f/p. still no start. Checked fire to end injector on passenger side, had fire. Removed injector wire on driver side injector by oil fill hole. spun motor to check for fire and had fire, the car started and continued to run. Plugged in injector and the car cut right off, did this several times each time the car cuts off when the this injector is plugged in. This is new to me. Will somebody explain this to me? Will a new injector correct the problem? Thanks, Steve:banghead:

That is a new one.....you were lucky that you just happened to pick the right injector.....

What bothers me is, injectors are not intermittent.....when they go bad, they stay bad........they are not ok for awhile.....and then go bad again....

You can do an ohm check.....your injectors should ohm out at 12 ohms on a cold engine......check all three on the front bank for comparison......if the suspect injector is the same as the other two, it could still be bad, flow wise, or injector coil wise......however, if it is much lower than the other two, it could be drawing too much current, and the PCM driver for it might kill the engine.....

Make sure the harness to the injector, that is the problem, has no wear thru marks that might short out the circuit, as you move it(mice are famous for getting under that cover and eating insulation)...also before installing the injector harness to the injector, move the harnesses that are attached to it, to see if the engine dies....there could be a short elsewhere that moves as you move the injector harness....

Since no DIY'er has any injector test equipment to check current flow and fuel flow, you can try this....pop off the fuel rail and swap the injector with another.....If it doesn't start and you remove the harness to the suspect injector, and then it starts, you know it's the injector.....if you remove the original harness of the suspect injector, on the swapped injector, and it starts, then it's the circuit to the harness(I would be pulling the PCM out of the air box to see if a mouse nest is there)....

Did you check for codes to see if a code was set for any injector driver circuit?

I assume you meant 3.8......

Excellent advice Tech11!

Well actually I listed it as a 98 model when it's a 88 model with the 2.8 engine, yes 2.8. Switching the injectors is what I intend to do to see if the problem follows the injector.

Well actually I listed it as a 98 model when it's a 88 model with the 2.8 engine, yes 2.8. Switching the injectors is what I intend to do to see if the problem follows the injector.

Yea I guess we were "lucky" but that was the only 2 we could get to with the intake in place. LOL. :biggrin:

OK, I replaced that injector and the problem appears to be corrected, I still don't understand how but its riding again. Thanks

The old injector checked @ 7ohms

Yeah, the 2.8 threw me.....no way that engine is in a '98......so I thought it was a 3.8.....

An '88 with a 2.8, is a completely different animal......I wasn't sure if the engine would shut down with one bad circuit.....in a '98 3.8, you have sequential injection, so one bad injector should only shut down one cylinder....

However, on a 2.8, you have what is known as a multiport engine......1-3-5 injectors are fired by one driver in the ECM.....2-4-6 are fired by another driver.....so one bad injector, drawing too much current, will cause the driver to shut down not just one injector, but all three.....

Next time, easy way to ohm these injectors, is ohm the harness to each set of injectors......as I said, an injector is usually 12 ohms......but because they are in parallel, when you ohm the parallel circuit, you will get a reading of 4 ohms(12 divided by 3)......so if you get a reading higher than 4, than you probably have an injector with high resistance or is possibly open.......for example, if one injector is open, you would get a reading of 6...if two open, 12.....

If you have an injector that is shorted, you get a reading near zero.....if one injector is much lower than twelve, let's say 6 ohms, the total resistance of the circuit will be 3.0 ohms.....

So by knowing what the resistance should be, your reading will tell you if an injector resistance is shorted or low(below 4), or if it is high or open(above 4).....without removing the upper plenum....

Yeah, the 2.8 threw me.....no way that engine is in a '98......so I thought it was a 3.8.....

An '88 with a 2.8, is a completely different animal......I wasn't sure if the engine would shut down with one bad circuit.....in a '98 3.8, you have sequential injection, so one bad injector should only shut down one cylinder....

However, on a 2.8, you have what is known as a multiport engine......1-3-5 injectors are fired by one driver in the ECM.....2-4-6 are fired by another driver.....so one bad injector, drawing too much current, will cause the driver to shut down not just one injector, but all three.....

Next time, easy way to ohm these injectors, is ohm the harness to each set of injectors......as I said, an injector is usually 12 ohms......but because they are in parallel, when you ohm the parallel circuit, you will get a reading of 4 ohms(12 divided by 3)......so if you get a reading higher than 4, than you probably have an injector with high resistance or is possibly open.......for example, if one injector is open, you would get a reading of 6...if two open, 12.....

If you have an injector that is shorted, you get a reading near zero.....if one injector is much lower than twelve, let's say 6 ohms, the total resistance of the circuit will be 3.0 ohms.....


OK so what does the replaced injector 7 ohm reading mean? thank you for the information.