Hi all, first post but I've been a lurker for quite awhile and have learned more than I could've ever imagined. On to the good stuff...
My 91 YJ manual 4.0 has been parked for several months due to a broken weld on the radiator support. Since parking it I have started it at least once every week or two and warmed it up to temp and it has always started without issue... Until today... The day I have multiple buyers showing up at my house with cash in hand ready to buy. The worst possible day.
With the key to ON its situation normal. Lights on, gauges do their dance, fuel pump primes. Turn to start and nothing. Nada. Not even a hint of anything.
The battery is an older blue top but tests good. Starter is a couple months old and also tests good. Popped in a new starter relay. Still nothing. Checked fuses and they appear ok. I have an ignition switch ready to go but I ran out of daylight and no shop lights.
Anyone have any other suggestions? Beer of choice to the winner if you're ever in the greater Baltimore area!
Tried jumping the starter... Spools up but doesn't engage. I know I'm missing something here. Swapped the "new" starter relay with a known good one and there's no click upon turning the key to on. Unfortunately electrical issues are not my forté and the only tools I have to diagnose such issues are my hands, eyes, and ears.
Is it worth trying to replace the CPS before I drop the steering column to go through ignition issues?
Is the engine even turning over (cranking)? Cause if not are are no sensors that keep it from cranking except for a neutral safety switch. And as far as I know YJs don't have one. On TJs you just have to push in the clutch and it should crank. But if you have no crank check for power and ground at the starter with it bolted to the engine. As long as you have both and the starter still doesn't engage but turns, the starter is bad. Search through youtube there are plenty of videos that explain starter troubleshooting.
The starter is a couple months old. Took it in and it tested good. I jumped it and it spooled up but didn't engage the flywheel. I don't think there's power getting to the starter relay. I've replaced it with a new one and also swapped it with a known good one and I get nothing out of it either way when I turn the key to on.
You can try some electrical contact cleaner and a small pipe cleaner and clean the relay contacts inside the fuse box then put some contact jelly down in there try and keep the water out. Also correct me if I'm wrong but there is three connections on the starter when you replaced it correct? Should be ground, 12v power source (straight from battery), and a third only gets power while the key is turned. Check these to narrow your problem down.
Going to try the contact cleaner tomorrow. I'm also planning on checking power and ground everywhere I can.
I have a general idea of how the whole ignition system works and the path it takes but like I said electronics are not my specialty... that being said, would a bad starter/solenoid cause the relay not to click when the key is turned to ON or is it vise versa?
Check you battery cable connections, power lead to the starter, and ground cable connection from the chassis to the engine. Appears the chassis is getting power but the starter is not. One of the main culprits in these cases is a bad ground because when you test things the ground problem is bypassed.