94 Jeep Wrg. Intermittently does not start

jeep
wrangler

#1

Hello…
I have an older Jeep that has been sitting a lot. I started it yesterday after about a month, it started up so-so, then once warmed up seemed to run fine. I took it on an errand and when I tried to start it up again, it was dead. The accessories worked, but engine did not turn over…after trying for about 10 min, I called a tow truck. An hour later the Jeep was dropped off at home, I tried again, and suddenly it started just fine. 1st try.
This morning after a cold night, I went out to try it…again, started right up. I let it warm up for a bit, then took it for about a 1/2 hour drive, even on freeway for about 10 min.
When I got home, I turned it off…after a min I decided to try again, and this time, NOTHING. Dead. Same symptoms as first time.
Could this simply be just a battery issue?

Known issues:
Catalytic converter does need to be replaced.
Battery is definitely old (7-8 years), it did sit a lot over last few years.
Transmission was replaced about 3 months ago.

I appreciate any help / suggestions.


#2

That’s an old battery. Without testing the entire charging system, you can’t say it’s definitely the battery, but that battery has likely hit the end of its life. It’s still not a bad idea to take it in to have the system checked to make sure there isn’t anything else going on with the starter or alternator, but I would put money on the battery given that it’s 7-8 years old.


#3

the very first thing you do is replace the battery

That very well might be the one and only problem


#4

Bad neutral safety

GORILLA TAPE


#5

Replace the battery and check the neutral safety switch. My son has a 98 Wrangler and we have started having problems with corrosion of the connections in the fuse/relay box. A year or so ago we lost the headlights, traced it to the fuse box. The wires coming up under the box to the fuse connections corroded and opened up. I was able to wire around that. Six months ago the starter stopped working. Jumping direct to the battery showed the starter worked. After messing around we could not find/fix the problem in the fuse box. Relay was clicking but no juice coming out. Neutral switch OK, Nothing obvious. We wired around it and now have a new momentary switch on the dash that runs from the battery to the starter. Turn the key to run, push the clutch in and bump the switch and it starts. At this age we try to fix it right but after a while diminishing returns calls for work arounds.


#6

Thanks for replies.

I went out and got a new bat. Although it needed it, that wasn’t the problem. Still power to acc. / lights but engine will not crank. I’ll look into the neutral safety switch tomorrow…will have to read up on it.


#7

The neutral safety switch operates through a relay. If you pull the START relay and look at the numbered pins you can test the neutral safety switch, the ignition switch and the starter by testing the sockets that the relay plugs into. BATTERY voltage should be at pin 30 key on or off, pins 85 and 86 trigger the relay to carry current from 30 to 87. Either 85 or 86 is grounded through the neutral/clutch switch and other is hot when the key is turned to the start position. That relay is the most common relay I have ever dealt with and from model to model the 85-86 connections vary. If there is a pin 87a it is a default connection from 30 that is open in the relay box.

With a test light, and an assistant to operate the key and clutch/shift lever the problem can be somewhat quickly diagnosed. It may be the relay that is failing but the neutral safety switch is the more likely problem if you have an automatic. It’s expensive as I recall and if it is bad it can be bypassed.

correction- the AT neutral switch is less than $30 and is easily replaced on the 94 model.