04WJGuy

Well I've got an interesting problem with the WJ.

I went to start it yesterday and it was as dead as a dodo, not even a click off the starter. Got a boost and let it run for about 15 minutes. Put it in drive and it died instantly, jumped it again and this time had to keep my foot on the throttle to keep it from stalling. Took about 45 minutes before I could take my foot off the pedal.

Checked the voltage at the alternator and it's good, battery is now a doorstop, installed new battery and it's constantly over charging 14.2- 14.7v. Last night after work I let it idle for about 10 minutes and suddenly the RPM's jump from 650 to 1000 after a minute comes back down to 650. A couple minutes later it jumps to 1500 then drops to 1000 then back up to 1500 etc...

All the ground connector are tight and didn't spot any loose or unattached wiring, battery cables are clean and tight also.

So guesses, is it the alternator going, PCM acting up (voltage reg), bad battery, or battery temp sensor going.

Dan

04WJGuy

While searching for an answer to my problem, I came across an interesting item on how to get 2 bastteries to fit in the space of one on the WJ's and TJ's, in the write up the guy stressed that the battery sensor had to be touching the battery to read properly. So I went out and tipped the battery on it's side and after a couple of starts the voltage is down to normal now. Problem solved.

Don't tip a regular battery over, I'm using a Optima yellow top which is completely sealed.

CrazyWJ242

thats pretty interesting, your refering to the circular springy thing below the compartment...

i was thinking of relocating (and adding) both batterys to the back in the spare tire carry/ utility drawer its going to end up becoming... i imagine that would become a nightmare later on...

04WJGuy

That's the thing that was screwing everything up, so if your going to relocate both to the back your gonna have to re-wire the sensor to the back to.
Going to try to stack both batteries up front. Pull the tray and make 2 new ones, one on top of the other.

CrazyWJ242

I've got a standard cell, 875 CCA Duralast Gold, over 1000a reserve... but think i might go to a pair of deep cycles, especially if i get a winch and all those lights...

04WJGuy

I was thinking of putting a battery in the rear well to (lights, winch, stereo, etc) and then while looking around the engine bay it looks like if you lay the battery on it's side there should be just enough room to stack 2 in the one space. When I get some free time I'm going to measure it up and see. Looks tight but it just might work. Will just have to build a new tray for the two batteries and I was thinking of mounting the sensor on the side.

CrazyWJ242

below the battery tray is the cruse control module, so you could move that if you deem it unnecessary remove it entirely... but yea i do think it would be close fitting the two batteries stacked... although the current battery could be slightly taller...

04WJGuy

The Optimas are about 1" taller but there only 3/4 of the footprint of the stock battery, so if you put 2 in on thier side it would actually sit lower than the stock one. The vaccumn line and wiring for the cruise module are the only things that appear to be in the way for now.
Going to pull the tray out this weekend and take some measurements.

04WJGuy

This is pretty close to what I was drawing up for the box. Made by ruffstuff.
I've got a 2'x 3'x 1/8" sheet of stainless in the shop, I'll just have to see if I can borrow or rent a tig welder for the weekend

CrazyWJ242

oooh thats pretty!

See i need to start hanging around my uncle some more, cause he has the keys to an amazing shop with everything you could possibly need inside... everything but a CNC machine...