help diagnose my no start

[XJ_ranger]

are you getting spark to the dist? are you getting spark at the plugs?

power to coil nothing past that

good coil

what plugs into the coil and controls it?

 

[langer1]

 

[Jeeper Creeper]

I posted the same issue a couple of weeks ago on my 91 and have not been able to figure it out. I was driving it yesterday just fine and today when I go out to work it turns over and no start. I am going to replace the pick-up in the distributor and see if that may resolve this. I have also replaced the CPS and tested all the wiring with no success. I will let you know if the pick-up fixes it. Good luck!

 

[XJ_ranger]

so i have a bad computer? great!

 

[RNMedic]

okay look at this wiring the yellow wire in is from the ECU and this is the signal from the CPS, If you have power to the coil and no power out AND you know the coil that you replaced was good then something in there is an issue I would go with the ignition module right below the coil. I don't think it is the cam sensor cos you ain't getting juice in the Dist therefore no juice out. If this image doesn't come up then someone will need to tell me how to post PDF files, John.. Good Luck I'll email it to you

 

[XJ_ranger]

okay look at this wiring the yellow wire in is from the ECU and this is the signal from the CPS, If you have power to the coil and no power out AND you know the coil that you replaced was good then something in there is an issue I would go with the ignition module right below the coil. I don't think it is the cam sensor cos you ain't getting juice in the Dist therefore no juice out. If this image doesn't come up then someone will need to tell me how to post PDF files, John.. Good Luck I'll email it to you

opiebennettATgmailDOTcom

 

[RNMedic]

coming your way. GOOD luck

 

[8Mud]

I'm not real familiar with the 91 but the system is generally fairly universal.
Check for power to the ICM with key in the run position.
Check for power to the ICM with the key in the start position.
The dwell/spark wire is the trigger. Or controls the whole process. Can't really be tested at home, reliably.
Possible the ICM is faulty. Possible the coil is open. Possible the power wire, the dwell/spark wire, or the ground wire is open.
Possible the ECU isn't triggering the dwell/spark pulse. Possible reasons. The ECU is lacking a necessary input, so it can trigger. CPS or wiring (common), here is where it gets tricky, what are the necessary inputs for the ECU to trigger the dwell/spark? Some inputs will default into open loop, some won't.
If you can pull the codes by the key cycle method it might help.
Probably the first thing I'd do, is swap some relays around, thinking a power circuit to the ECU or a necessary sensor loop is interrupted. I'd probably check the fuses for the same reason. Then check the power to the ECU (or ECM whatever it's called). Check the basics, before you start with the exotic.
If anybody has an idea of the *Necessary* inputs for the ECU to trigger the dwell/spark, now is the time to jump in. Some inputs are absolutely necessary, some will default if not present.

 

[davedanger]

Using an AC voltmeter check for a signal at computer from crank sensor. you might also check true fuel presure with a gauge. A rare problem but check wiring behind left front turn signal, fuel pump feed wire (org/blk) splits and runs forward thru radiator suport (behind turn signal) and across radiator.

 

[brtb]

Hope that was a joke.

Well it's either that or the muffler bearings...

 

[XJ_ranger]

Well - I got the 91 to run - turns out the Auto Shutdown relay contact in the relay pannel got pushed down and wasnt contacting the relay.

so even though i tested the relay and it was good, the conection there wasnt...

thanks for everyone's help!