Getting no fuel

[Slo2gn]

For the longest time my injectors have not been pulsing or spraying fuel.. I know that fuel is going through the rail because I have a AFPR on the return side I pulled the line off and fuel was in the rail I reattached the line and pulled the rail with the injectors still on the rail and had a friend crank the car over and no fuel came out.. (just to clarify I have a 97 2g NON EPROM ECU W/OUT LINK.. Stock Injectors) So finally It spit a code after a month! Pulled a p0202 "Injector Circuit Malfunction"

during the last month I tried changing known Good: injectors, resistor boxes, ECU'S, and MPI relays that came out of running 2g's

Any Idea of how to address the P0202? thanks for any help or input you provide!!!

 

[toddrs93]

If there is power at the resistor box? Does the car have spark? Should be a red wire at the resistor box that's positive.
Ecu then controls the ground side of the injector, so if you have tried a known good ecu, and you have spark, then I would say it must be a wiring issue. If there is spark then its probably an isolated problem in the injector circuit, if not then I would say something more in the ignition circuit, or crank/cam signal, etc.

 

[steve]

No sense in rehashing what was covered before http://www.dsmtuners.com/threads/no-injector-pulse-or-power.496955/#post-153544090

http://www.dsmtuners.com/threads/p0202-issues.430759/
http://www.dsmtuners.com/threads/p0202-code-curiousity.461294/

 

[Slo2gn]

No sense in rehashing what was covered before http://www.dsmtuners.com/threads/no-injector-pulse-or-power.496955/#post-153544090

http://www.dsmtuners.com/threads/p0202-issues.430759/
http://www.dsmtuners.com/threads/p0202-code-curiousity.461294/

Agree'd however since the topic changed and I ran all of the test's with zero issues and zero responses I figured since I got a CEL I'd start a new thread.. and the other p0202 threads really aren't pertaining to my specific set of issues I could re-post my specific issues in that thread.. One of them states he has an issue with #2 injector the other seems to cover not a lot at all.. I have an issue with all 4 injectors that came on suddenly.. I have been looking on here for about an hour I am trying to figure out how to find a short in the injector circuit with a Digital Multi meter is there a write up on that I have been watching you tube and some other various searches on google ..

 

[steve]

There are four injector circuit fault codes on the DSM (there are others for engine with more cylinders) P0201, P0202, P0203, P0204. Each point to a specific cylinder. You may get more later but for now your code is pointing to a problem with the injector circuit on cylinder 2.

Your other thread is important history even if it did go off track, and my linking it was to avoid Todd asking question that had been asked before. Given that you still have a problem many of them perhaps should be revisited and verified again. You started with:

I ran a test light to all the injector pigtails and, there was no power to all 4 injectors..

The injector circuit isn't too complex.

You have verified that the MPI circuit manages to power the ECU and that you're getting some spark, so the next step would be to check at the injector resistor to see if you have power feeding it and from there power to each of the injectors. The ECU provides a switched path to ground to the other side of the injector to fire it.

I don't know if you measured the voltages at the injectors or just tried a test light between the terminals.

If you don't have a copy of the FSM for your car you should at this point. I can help explain the diagrams and what tests might help you decide as you diagnose things.

 

[Slo2gn]

There are four injector circuit fault codes on the DSM (there are others for engine with more cylinders) P0201, P0202, P0203, P0204. Each point to a specific cylinder. You may get more later but for now your code is pointing to a problem with the injector circuit on cylinder 2.

Your other thread is important history even if it did go off track, and my linking it was to avoid Todd asking question that had been asked before. Given that you still have a problem many of them perhaps should be revisited and verified again. You started with:



The injector circuit isn't too complex.

You have verified that the MPI circuit manages to power the ECU and that you're getting some spark, so the next step would be to check at the injector resistor to see if you have power feeding it and from there power to each of the injectors. The ECU provides a switched path to ground to the other side of the injector to fire it.

I don't know if you measured the voltages at the injectors or just tried a test light between the terminals.

If you don't have a copy of the FSM for your car you should at this point. I can help explain the diagrams and what tests might help you decide as you diagnose things.

I did run a basic power test with the key turned to on with a digital volt meter to the injector pig tails and with the key on I was seeing 12.3 volts at all 4 pigtail on cranking the voltage did see a drop However I will rerun the test with the FSM I have the hynes and the chilton ill look into the testing procedures and see what I come up with. thanks for the help

I did find this diagram of the circuit I am not sure if it is 100% correct can someone with knowledge verify this?

 

[steve]

http://www.dsmlink.com/images/forums/2GECUMFI.pdf See page 8.

 

[kjlinwi]

It sounds like there is no trigger to your injectors. Think about breaking your problem into inputs and outputs. Right now you have no idea if your injectors are being turned on (triggered) this is considered output. To test, koeo (key on engine off) use a 12 volt test light- not a volt meter - and backprobe the injector harness connectors. Use either a purpose built backprobe or a sewing t pin and slide them into the connector. Both terminals should turn on the test light. If one or more injectors doesnt light up on both terminals, disconnect that connector and verify light on one terminal. If you have light, then the injector is bad.

If all the terminals (all 8 of them) light up koeo, then you will want someone to crank the engine while you retest all 8 terminals. Now on each injector you should have steady test light on one side and flashing test light on the other terminal of the same injector. They do make a special tester to do this called a noid light but you dont need it.

Based on your description and on whats been done already, Im betting you will have all good results but no flashing light on any of the injectors. You will then need to pull up a wiring diagram and repeat this test at the ecu. Your looking for the output signal from the ecu to the injectors on the four wires. You do this to eliminate the poss of a wiring harness problem. If you still get no flashing light at the ecu (remember to back probe. Do NOT pierce wire insulation it will come back to haunt you) then you will need to check inputs to the ecm.

You can post back with your results and i can walk you through that test as well.

Hope this helps.