: Fuel Injector problem



Pete315
07-30-10, 01:44 PM
On my 95 Eldorado, I was getting code P119. I did the PCM override test #4 and found out #3 fuel injector was not working. I replaced injector and car was running fine. I just code that code again P119. I did the test again and found out it's #3 again. I used a long screw driver and place one end on each of the fuel injector and listened. #1,#5,and #7 were ticking loud thru the screw driver. #3 was not. I switched #1 and #3 fuel injector and still #3 is not ticking. The original injector that was in #3 now in #1 is ticking away. I know there is gas going to #3 because the top o-ring got cut a little and now is leaking gas. So it has to be the wiring. Is there a way to test that connection using a test light? is one wire hot and the other ground? could I jump one of the other fuel injector connectors with this one? All the wires are wrapped in electrical tape and appear to be in good shape. It would be almost impossible to see if there was a short with that #3 injector wire.

Submariner409
07-30-10, 01:47 PM
Fuel injectors are timed and pulsed exactly like the spark plugs: swap or parallel a wire and you get broken engines.

Find the wiring fault. If the code cleared then came back it's possible that one of the connector pins/socket is bent/dirty.

Pete315
07-30-10, 02:22 PM
that's what I figured. looking at the manual, I might need a fuel rail harness. That's the only thing it could possibly be.

Pete315
07-30-10, 08:57 PM
where can I purchase a new fuel rail harness? dealership?

Pete315
08-05-10, 11:27 AM
It was the fuel injector harness. Got a used one off EBAY, now runs mint. No ore P119 codes.
The onboard computer and shop manual are great.

Pete315
08-12-10, 12:11 AM
well, I got that P119 back, and it's fuel injector #3 again. I'm 99% sure it's not the harness. I followed the instructions in the shop manual. I removed the electrical connection from #3. I do have constant power to one of the terminals. I checked another injector that is working and get the same power to one of the terminals. I used a screwdriver to all the injectors and can hear a loud clicking to all except #3. I even put #1 connector onto #3 for a second and then got a good clicking from #3. So I don't think it's the fuel injector or the harness. What else could it be? It was working at idle but once I revved up the engine, the injector stopped working. Now I can't get it to work again, even at idle. What tells the injector to inject gas at a specific time? Is it the PCM? Please help, I got a 7 cylinder Northstar with new head gaskets installed by Northstar Performance.

Ranger
08-12-10, 12:35 AM
I even put #1 connector onto #3 for a second and then got a good clicking from #3. So I don't think it's the fuel injector or the harness. What else could it be?
Bad injector.


What tells the injector to inject gas at a specific time? Is it the PCM?
Yes.

Pete315
08-12-10, 01:02 AM
tomorrow I will switch #1 injector that I know is working with #3. If #1 which was working for Cylinder #1 now stops working in #3, then what should I do next?

Ranger
08-12-10, 01:09 PM
Assuming that there is no short or open in the wiring to #3 I'd guess that you'd need a new PCM.

Pete315
08-12-10, 05:43 PM
that's what I'm thinking. I think I'm going to run a test wire from the PCM terminal 1A3 which is for the #3 fuel injector directly to the B side terminal of the injector. The shop manual is a little vague with the wiring of the injectors. with car off and key in run position, I get constant power to one of the injector terminals. I'm assuming when the PCM tells an injector to turn on, it sends voltage to the other terminal. Am I right? I did check 1A3 on PCM and I do have power.

Ranger
08-12-10, 11:33 PM
I think you are right, but I'm not positive enough to say for sure.

Pete315
08-12-10, 11:55 PM
well, I just bought a PCM off EBAY. same numbers and 4 letter code. according to the shop manual, with the tests I was able to complete ( I don't have an OHM meter) it has to be either the injector, the harness or the PCM. I ruled out injector. I really doubt the used harness I put on had the same problem with the same #3 injector. That leaves me with the PCM the blame. I'll keep my fingers crossed and keep you guys posted.

Ranger
08-13-10, 11:37 AM
You may have to have a dealer reprogram the PCM to your VIN. I'm not positive about that though. Just something to keep in mind if you have any problems.

Pete315
08-13-10, 06:41 PM
I thought starting with 96 the PCM's had to be programmed to the vin. I may be wrong though.

Ranger
08-13-10, 11:41 PM
:noidea:

Pete315
08-17-10, 01:10 AM
I changed PCM and problem is gone. Runs mint. No P119 code. Just what the shop manual said it should be.