No start - Injectors won't fire

[KMT]

I did re-wire that melted plug even though I did not know what it was for.

Got it, thanks.

I have pulled the injectors and am going to take them in to get tested.

You can test them yourself with a volt/ohm meter - check resistance between the terminals. Just check they are all nearly same. I doubt they are the issue, tho, and no need to pull just to check. I'd out new o-rings on them since they're out.

There was a short in the cam sensor / crank sensor wiring so perhaps that fubar'd my injectors.

No signal, no signal(s), no run, so... Are you replacing that harness, or trying to DIY repair? Can be tricky... I'd source a good used one that hasn't seen trauma.

Sorry if I missed it, is the upshift light staying on while cranking the motor over? Did you confirm the balancer isn't wobbly/loose? How did that harness get shorted/damaged?

I will post the results once I get the injectors back.

Good luck.

 

[sdw]

Got it, thanks.



You can test them yourself with a volt/ohm meter - check resistance between the terminals. Just check they are all nearly same. I doubt they are the issue, tho, and no need to pull just to check. I'd out new o-rings on them since they're out.



No signal, no signal(s), no run, so... Are you replacing that harness, or trying to DIY repair? Can be tricky... I'd source a good used one that hasn't seen trauma.

Sorry if I missed it, is the upshift light staying on while cranking the motor over? Did you confirm the balancer isn't wobbly/loose? How did that harness get shorted/damaged?


Good luck.

I got a new harness from John Ludorf and replaced it.

Following the no start guide got me to that point.

There is no upshift light on cranking though I replaced my crank sensor with my spare just to be sure.

I have spark and my noid light flashes on each injector.

Given I have spark and a signal to the injectors I should think I get at least a cough out of the engine. Maybe the short damaged the injector coils. I will ohm them first before taking them in.

Sean

 

[DOUG H]

Did you not check them all before (May 15th) & they were all 11.5-12 ohms?

 

[plethaus]

I got a new harness from John Ludorf and replaced it.

Following the no start guide got me to that point.

There is no upshift light on cranking though I replaced my crank sensor with my spare just to be sure.

I have spark and my noid light flashes on each injector.

Given I have spark and a signal to the injectors I should think I get at least a cough out of the engine. Maybe the short damaged the injector coils. I will ohm them first before taking them in.

Sean

That is strange that it won't run despite injectors ostensibly working, fuel pressure in the rail, and spark at each plug. At that point I would think some sort of timing problem (injector or ignition) related to the cam and/or crank sensors. It might be a good idea to pull the cam synchronizer out at this point and verify it's in good shape.

 

[DOUG H]

I was always under the impression that it would still start with a bad cam sensor signal, it may just take 3 attempts as the computer tried 1 of 3 different stratagy's. No crank signal & you get nothing. Is that true?

 

[sdw]

fFnally was able to get to my rented garage.

Man I wish I had a garage at home!

ohm’d the injectors they range from 10.74 to 10.95.

everyone one of them switches.

I guess I will start again with the “no start” checklist.

super frustrated.

URGH!

 

[TBirdSC89]

This sounds incredibly frustrating. I'd check the ignition switch too while you're at it, the battery terminals and wires, starter and wires. I'm definitely not an expert but when nothing makes sense to me I go back to the basics

 

[DOUG H]

Wow, I'd be frustrated as well. It sounds like you've got everything you need in order for it to start/run.
Spark at the plug's, fuel pressure in the rail,signal/pulses to the inj's & the injectors themselves check out.

The only thing I can think of thats left is the quality of the fuel or the mechanical condition of the basic long block assembly itself.-lack of sufficent compression. You would think it would still do something though, some type of kick or cough in the intake or exhaust or some type of indication it wants to start. Even if ignition timing is off. Maybe it is the gas itself?

 

[sdw]

Wow, I'd be frustrated as well. It sounds like you've got everything you need in order for it to start/run.
Spark at the plug's, fuel pressure in the rail,signal/pulses to the inj's & the injectors themselves check out.

The only thing I can think of thats left is the quality of the fuel or the mechanical condition of the basic long block assembly itself.-lack of sufficent compression. You would think it would still do something though, some type of kick or cough in the intake or exhaust or some type of indication it wants to start. Even if ignition timing is off. Maybe it is the gas itself?

Sorry to be so long in replying.

I haven't been able to get to the garage in a month so have not continued my search.

Compression is excellent, I was on my second fillip when it died so Gas isn't an issue.

I will try to get motivated again this January once the snow is gone and really try to get this thing going.

Sean

 

[Truebird sc]

If you have spark and you have fuel and signal to ur injector either they are clogged up witch I highly thought but Is a possibility if u put bad fuel . I had a similar issue on a motor swap I did but in my case the motor sat for a long time and injectors needed to be clean . The noid tester help me figure that out. I would check for fuel in ur spark plug if is wet then ur firing order is off if is not then ur not getting Fuel . Hope it helps

 

[Mranalla07]

My '91 5-speed died when going over a speed bump.

I have looked for a connector that came apart but have found nothing. I have spark, and fuel but the noid light did not flash when I checked the injectors.

I changed the crank sensor to one of my spares but no change. Changed the IRCM to a known good one, no change.

The car is modified and has a BHJ balancer and a QH chip, etc, etc.

I am not sure where to look now.

My grounds are good including the the one at the back of the drivers side head.

Is there a way to test the EEC?

There is one connector under the car attached to the transmission support that is melted from where it must have hit the exhaust. But the EVTM and wiring diagram has no info on it. My EVTM is at my garage so I can't give the page number but if you find where the two connectors go into the transmission you will see it pictured attached to the tranny support bracket. The connector has an end plug on it, but I have no idea what it is for.

Any suggestions would be appreciated.

Sean

Any updates ? I am having same issue!

 

[DOUG H]

After reading the post started by you a hour ago, you are not having the same issue as SDW.
You &/or your brother are doing what I call swapnostics rather the diagnostics.