Crow Horse

Geez,it never ends. I just replaced my negative battery cables, one to block, one to fenderwell , and the block to firewall. Cleaned all connections, used Ox Guard to prevent corrosion and now I have a no start condition. Battery voltage is 12.29, it cranks and wants to start but no joy. It actually cranks better than ever but that is of little consolation at this point.

All lugs were properly crimped and used Ox Guard and adhesive lined heat shrink.
I'm at a loss as where to look next.

A similar issue happened not too long ago when I had the head replaced. I had it towed to the dealer and the next morning they started it without issue and drove it into the shop.

Any ideas? I am getting spark. I used an inductive timing light to verify this as I was doing this alone.

CCKen

Was everything okay prior to reworking the ground cables?


Did you make sure the small wires at the coil mount studs (G101) were attached securely?

Crow Horse

Other than the previous incident of no start, it was fine. G101 were cleaned and secured. Could a faulty battery cause this. Its 5 years old and when cranking the voltmeter basically doesn't move. When I just turn to the on position it does move up to about 12 volts...

Crow Horse

Ive read that low battery voltage can really mess with XJ starting. Could it be that the battery under load isn't up to snuff?

CCKen

Yes, a bad battery can cause your issue. The PCM needs at least 9 volts to function.


a five year old battery was on borrowed time two years ago.


If it's a wet cell battery, have you ever checked the electrolyte level?

CCKen

What did you end up doing for a fusible link?

Crow Horse

I was just replacing the grounds so I didn't get that far. I'll replace the battery. I did check and add some distilled water several weeks ago.

I have to reread your post on my other thread. Lots of info to wrap my mind around.

The two other grounds on the block under the coil, what circuits are they for?

BlueRidgeMark

A 5 year old battery at rest that is showing 12.29.... possibly a bit suspect. Still, if it's spinning over that nicely, it's probably not the battery. OTOH, what's the voltage while cranking? That's where the rubber meets the road. You can get a free load test at Autozone or Advance. Not a bad idea a with a battery that old.


But if you have spark, I'd want to see a fuel pressure test, if the battery checks out okay.

Coincidence does happen, and there are two mistakes you can make about it:

1. Assume it can't happen, and only look for something that relates to the work you just did.
2. Assume it must be coincidence, and only look for things that don't relate to the work you just did.

Couldn't hurt to check that fuel pressure.


How's the spark, though? Good and strong?

Jeep Driver

Something came unplugged.
Check your CPS plug/connector.

madmanmarty

I had this happen.

CCKen

See pic. Important goodies there.

Crow Horse

Installed a new battery. No joy. Installed a known working coil. No joy.
I'm going to go over everything. One item that could be the culprit is the other ground that shares with the main battery ground on the block. When I tightened the nut, it spun to the other ground mounting bolt. I'm wondering if it stressed out the wire causing an internal break. I'll probably cut off the terminal, splice in a wire with a new ring terminal.

Crow Horse

Update- respliced the 2 grounds that were in question. Pulled plugs and they were wet. Blew them off. Checked cps and that passed. It really cranks and comes so close to starting. Running out of ideas....

Crow Horse

I'm getting spark but it wasn't blue and I thought it should appear stronger....What would cause a weak spark? I installed a working coil.....

aj2494

I know this sounds really dumb, but did you check the battery terminals and connections? I had a loose connection on one of my terminals that kept me chasing my tail for a while. Sometimes I would have no power at all, and sometimes it would crank but then not turn over. Rummaging around in there may have disrupted something.

BlueRidgeMark, I just would caution against taking the Advance/Autozone/etc. battery test as gospel. I had one store tell me a perfectly good battery was bad.