94 cherokee sport 4.0 with 96 engine...Hope all you guys are doin well!

So it has been quite a while. And I have not used my Cherokee very much. It is currently so unreliable I cannot afford to take it to work.
The last thing I did was replace the IAC valve just because I had a new one laying around. That did not change anything. The main problem is
she will start first thing, run and drive great...then you park and let her sit...won't start back up. Until like the next day or 4 hours later.
Even fluttering the throttle or full throttle doesn't work anymore. So I parked her for the week.
The following weekend I go to start and battery is dead. I get out my voltmeters(I have several) And she is reading 1.9 volts hooked up.
Disconnected the battery and it shot up to like 11 ish. Pulled the battery and she is perfectly charged now on my battery tender. This is weekend three.
My Dad is an old school electronics engineer so he was teaching me about infinite resistance. Still confusing. But he showed me last Sunday and we
deduced that I have at least a 1 amp drain that came outta nowhere..(well somewhere). I remember a while back when I was driving it certain things being
turned on would drop the charge voltage on the alternator gauge...like rear defrost that gauge would drop like a rock! Or front defrost when the compressor engages it would
start dropping. The headlights are off the electrical with the aftermarket KFAB kit and double relays so they have no effect. I don't wanna reconnect the battery until I find the problem.
My Pops said just connect the voltmeter and while checking the resistance start pulling fuses. I will probably do that today.
If anyone has any input regarding some of the symptoms, I would appreciate it.

Over time many things have been replaced, especially during the engine swap. All sensors except the O2 and MAF have been replaced. New plugs, wires, distributor, cmps, ckps, tps, Map, IAC. The Cat has been removed and there is
a welded straight pipe connected to a glasspack muffler.(Sounds mean as hell). Has Rotella T6 Synthetic with a Mopar Oil filter. Also brand new front calipers with slotted rotors(pretty awesome).
I would love to find this gremlin...it is getting really annoying.
Thanks again and it is good to be back!

 

Just for giggles, pull the plastic side panels in the cargo area and inspect the wiring there. If any water gets into the body there from rust or bad body welds, it can corrode the connectors and cause short circuits. I have rusted wheel wells around the flares and first my trailer wiring harness toasted itself. Then the other side wiring went up in flames!
It took me 2 months since Christmas working in the cold to get it fixed. Now everything is wire splices, not connectors. This all started with a 1.5 amp parasitic draw I couldn't locate.

 

Duplicate post

 

Thanks Dave I will definitely check that out. Probably the one place I have not looked yet but always wanted too. Here's to a shadetree mechanic weekend!

 

We've got your back!

 

"My Pops said just connect the voltmeter and while checking the resistance start pulling fuses."

Your pops is right but I think you meant he said Ammeter, not voltmeter. That will show the amps parasitic draw. Then start pulling fuses.

 

Yup. Also keep in mind you might see some initial current draw from the radio when you first hook up the battery. Discovered that on mine, it tries to eject any CDs when it's first hooked up. Turned out to be the glove box light was staying on in my case.

 

a test light is best between+ bat to lug, will glow brightly at 1amp, but not glow @30ma (radio, clock etc)

pull each fuse

 

Not so sure about that. The light itself might draw an amp also. Better off with a meter

 

No definitely meant voltmeter and resistance. He showed me how to do it. Ideally you want infinite resistance but obviously a tiny bit is normal.
This is with no battery connected and the voltmeter on the positive and negative leads. He showed me an equation...but I was just like just tell
me what I am looking for your science is too strong for me to handle!!! Perhaps I should say I call all meters voltmeters but ideally it is a multimeter and I am measuring ohms.
I can measure amps with it also...he read your post and said you can do it that way also. This was just the way I was doing it while the battery was charging in the
garage. So I essentially I meant to imply "Multimeter"

 

Lol Allright. So he is having a teaching moment by making you an ammeter with a voltmeter and a resistor. Only problem is you have to have everything just right, a sensitive volt meter and a hight resistance highly calibrated resistor. Then you have to do the ohms law calculation to figure out what the amps are.

 

Either I am not explaining this right or I type too much. It is not just a voltmeter, it is a multimeter. It measures voltage, amperage, and resistance...among other things. I just call them all voltmeters(which I shant not do anymore!) My pops is a retired electronics engineer...I grew up measuring things and soldering and taking things a part. There is a meter in every corner of our house haha. I think we have something to measure everything. I will be working on the jeep during the next couple hours.

 

I'm assuming that the discussion about how has continued because the common method of discovering usage when the battery should not be used is to disconnect the circuit and connect and amp-meter (multimeter) in line with the circuit. Disconnect fuses until the amperage drops. Whichever fuse is the culprit allows you to start combing that part of the circuitry for the drain.
Since amperage is a combination of resistivity and voltage, then of course there is more than one way to skin a cat.

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When we are done discussing the how, post which fuse is found to be culprit. Someone can likely post the schematics for that part of the wiring so that you can figure what is your drain.

 

Well said. Anyhow I found the fuse and it was labeled as I.O.D with some googling it is noted as the ignition off draw fuse. (20 amp) Once out there was literally no current draw. I threw the battery back in
And she started right up without the fuse. I lost my door locks, interior lighting, stereo, and I think that is it. But at least I can keep the battery in. The next test is to see if she will start after fully warmed up.
And of course to folllow the trail of wiring. But I can drive fine without that fuse.

 

That could be the overhead light, glove box, radio quite often.

You were pulling the fuses from the power distribution center in the engine bay, correct?

If so, then please replug that and continue the test while pulling the fuses inside of the vehicle from the fuse panel in the area behind the brake pedal. Post which one or ones of those also stops the drain. That will further narrow your search. I would guess Dome Fuse 10 AMP.