Ditto. Well under 2 is more like it.

 

Agreed. Tip 5 needs to be done!!!!

 

Tip five is complete. .2-.4 ohms from every sensor and on B11,B12,& D3 on the ECU. Still no spark. I rechecked the battery voltage (12v), the speed sensor (CPS), the sync sensor, and the start signal(12v). Those checked good.

I checked for pulses from my injector signals signals and I got nothing. (Although I did smell a hint of gas this time). I also checked my ignition interference signal and got nothing.

Any more ideas, or should I order my third ECU?

 

No more ECUs.

You said you have at least .5 AC volts at the ECU while cranking?

 

Yes. I have .54

 

I happen to have an almost new ICM I bought from Napa. Broken down in the rain that is all they had nearby. The coil I actually needed was 60 miles south. Anyway maybe take a look here, something I came up with some years ago. I DID try to duplicate this test with a $1 led from the $ store and it didn't work.

 

I'm still thinking this switch is something to worry about. I doubt it's your ECU as those are pretty robust. You sure you've got all your basic electrical connections intact? I'm worried that you are using a jerry-rigged starting method that's not making the right contacts when you have the key turned to START or RUN.
When your key is turned to RUN, do you hear the fuel pump prime? Do you have fuel pressure on the rail?
Might want to swap the fuel pump and B+ Latch relays (I think all the relays are the same) and see if there's a difference.

 

The switch is new. I am sure everything is connected. I don't "jerry rig" anything and I take it as an insult that you would suggest it. The fuel pump is fine I have fuel pressure and the issue I am trying to fix is the no spark problem. I don't want to come off as harsh but you basically called me an idiot in your post. I don't come here for that. I come for assistance, if it is offered.


I have changed out the relays with new ones that I had on hand. I changed all four. I checked the function of the B+ signals a few days ago and they were good, relay was working properly. I don't think that would keep me from getting the spark signal anyway.


The reason I keep going back to the ECU is because I have consistent good inputs and I have bad outputs. Getting a bad part from the auto parts store is not an unheard of thing, although I admit it is rare and even more rare that two would be broken in exactly the same way. I just don't know where else to go.

 

 

So, please remember we're here to help and use our own experience with similar issues to suggest things for you to try. Sometime people post that they put in a new ECU when they mean that they put another one they picked up at a swap meet or from the junkyard (which could be just as bad or worse then what they started with). Often people go in circles and are really sure they've tried everything but then go back and found something wasn't right. You posted the above and mentioned "hotwired". You also had a very high resistance on a ground that you thought was ok at 40 ohms but then went down to 0.4 ohms. I was only going by what you've posted and the picture showing lots of wire pulled out from under the dash.

The previous owner of my Jeep had installed an aftermarket remote car starter. It was a holy-hell trying to figure out what wires were stock and what was added. This forum helped me with my "no start" problem.

Just trying to help.

 

Is the ECU grounded well?

 

Since the ECU was pulled out and I was unsure about the case ground, and the need for it, I ran a jumper with alligator clips from the case to the ground connection under the dash. .2 ohms there.

I returned my second ECU because the 30 day return period was almost up. So now I just have the original ECU to work with.

 

My only other tip is to check or change the resistor on the drivers side fender. I broke one of them in half by accident one time and didn't realize it at the time but it caused a no spark condition. Before you ask, I had a pole under the hood to hold it up while I bolted it up by myself and it must have hit it lol. Took me a few hours to figure it out. And I hate to keep saying it but I really don't like the crank sensors. Just my 2 cents.

 

Since the ECU was pulled out and I was unsure about the case ground, and the need for it, I ran a jumper with alligator clips from the case to the ground connection under the dash. .2 ohms there.

I returned my second ECU because the 30 day return period was almost up. So now I just have the original ECU to work with.

 

Cruiser could power latch relay be causing this ?