Not starting in cold mornings, 90 Renix 6 cyl

Been having an issue lately after a cold night and trying to start it in the morning. It'll crank fine but I'm not getting a spark at the coil. Will mess with it for half an hour trying to crank it and then finally it just cranks up. Is this a sign of the coil going out? Or maybe the CPS?

Are you sure you are not getting a spark at the coil? Coil and CPS (CKP) failure is more often warm/hot than cold.

yep, pulled the coil plug off while I had my bud crank it and held it with the connectors 'bout half inch apart, no spark.

Sorry about the repeated questions, just trying to help. I don't understand "the connectors". To do this test, normally I would take the high voltage wire from the coil to the distributor and pop it out of the distributor. Take that end and hold it near a good ground like the head or block while someone cranks the motor over. When you say "the connectors", I can't tell if you mean the low (12 volt) wires instead of the high voltage one.

The three grounds at the dipstick tube are for the Ignition Control Module (ICM), Engine Control Unit (ECU), and the o2 sensor. Clean and tighten those grounds.

Also, the B latch relay controls power to the coil. When it won't start do you have 12v to the ICM? When in the no-start condition can you hear the fuel pump come on for 3-seconds when you turn the key to the ON position? You can try swapping the relays around, but mark them first so you will know if that changes things.

Yes I can hear the fuel pump start and by connectors I mean holding the coil plug 1/2 in from the coil. Is the B latch relay the plug that goes to the coil?

The B latch relay should be the third relay farthest from the firewall.

The ICM has the coil clipped on top of it.

If looking at the ICM from the driver's side of the vehicle, starting from the left a three pin connector, a two pin connectors in the middle, and an unused three pin connectors on the right.

The left three pin connector, from the left with assigned letters: C=Tach Signal, B=Ground(dipstick tube), and A=12v from ignition(through the B latch relay).

Check for 12v at "A" with the ignition on and a good ground through "B".

And yes, pulling the coil wire from the distributor cap and holding it to a good ground is fine. You want a BLUE hot spark.

might have to check it in the morn, jeep started up fine, drove it to work tonight (graves) and may end having to troubleshoot it to get home :doh:
thanx for the details

paulhead said:

might have to check it in the morn, jeep started up fine, drove it to work tonight (graves) and may end having to troubleshoot it to get home :doh:
thanx for the details

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Good luck.

Answer me a question, why do those have to be so deep? :confused1

half an inch is a pretty decent distance - remember that the spark plug gap is what, .02 to .035 of an inch? Try holding them closer together.