Topic: Weird starting issue with my Jeep

[95yjman]

I have a 97 TJ with a 2.5L, auto that has a weird starting issue. It seems to do it when it sits out in the cold at my work for 16 hours but it did it tonight for just sitting out for a total of 8 hours.

When it first did it, I thought the battery was low on voltage or something because it would crank but really slow. It was an old battery so I thought well winter is here and it killed my battery. So I just replaced it...with a yellow top. When it did it the first time, I also noticed the volt gauge and fuel gauge not coming on with the key on.

So now most recently, it did it again with the yellow top. However I know its not the battery now. The lights and everything are bright as ever, and..its a new battery. The second time it did it, again the volt gauge and fuel gauge weren't working. I also couldn't hear the fuel pump turn on.. So I towed it home with other Jeep but half way home, I got the TJ to start. Just out of no where and all the gauges came back to life.

So with all that being said, I replaced the crank sensor this past summer, when the crank sensor went bad, the volt and fuel gauge weren't working and I couldn't hear the fuel pump prime when I would flip the key on, and of course it would just crank and crank. Anybody got any ideas to what my current problem maybe? Did the crank sensor go out again? Can the cam sensor cause the same issues? I'm not pulling any codes, and the wiring to the crank sensor all looks good. Should I replace the crank sensor with a mopar one? I really need to get my TJ back on the road..

[grumpygy]

Just my opinion starter going bad.

[sharpxmen]

are there any other gauges or lights on the dash not coming on? does it crank at all and not starting or not cranking?

it's either what he ^ said (starter) or you have a bad battery connection or bad ground.

just to mention: fuel and volt gauges got nothing to do with the crank sensor

[dwtaylorpdx]

1. Started got toasted by using weak battery. (Need new started or at least need to rehab the starter.)
2. Check all the big grounds. (Ground spider on the block by oil filter is a biggy.)
3. Clean the connections on the fuse box.
4. Ignition switch.
5. Starter relay in fuse box.

[95yjman]

are there any other gauges or lights on the dash not coming on? does it crank at all and not starting or not cranking?

it's either what he ^ said (starter) or you have a bad battery connection or bad ground.

just to mention: fuel and volt gauges got nothing to do with the crank sensor

Yes it does, even says so in FSM.. For some reason it can (not always) cause those two gauges not to work.  Also I believe if the computer is not getting a signal from the crank sensor it won't send any fuel..

Just my opinion starter going bad.

If the starter was going bad I don't think it would crank like normal. It cranks normally just doesn't fire.

Just an update, I replaced the crank sensor with a mopar one, so far everything is fine.. We shall see. Thanks for the help and replies guys!

[grumpygy]

Fuel Pressure how is it.

[sharpxmen]

Yes it does, even says so in FSM.. For some reason it can (not always) cause those two gauges not to work.  Also I believe if the computer is not getting a signal from the crank sensor it won't send any fuel..

if you put the contact on do the fuel and volts show anything? crank sensor is not doing anything at that point - out of curiosity (I don't have a TJ so i can't test myself), unplug the crank sensor and put the key in run without cranking, based on what you're saying those 2 gauges should be dead - just wondering if that's the case (might be some weird PCM thing for TJs).