Thetastycat

What's so weird is it will start just *great* a few times in a row, then do all that weirdness. SO weird......so the guy at O'Reillys said it was weird that it was testing so high, like over 14v, almost like it was trying super-hard because it was going out. I didn't really understand that but the thing is 2.5 years old, so it wouldn't surprise me if it didn't last too long. This started pretty gradually a few months ago and is getting gradually worse. What I don't understand is how it will do that crap and then actually start normal, or vice versa.....cables look good and I replaced both terminals recently, so I'm fresh out of ideas on that one......

awg

a cable can look good , but be no good, including earth cables

with those symptoms, you would almost certainly have to replace them first

battery should be load tested

starter is not beyond suspicion

btw, and I love to say this...always stuff rags in the the "chest" of an open engine cover...I knew I was safe stuffing a rag into that hole so the bolt cant fall down there

had a spanner bounce down into the timing chain area of an engine once

Thetastycat

OUCH...bet that was a no-fun moment too At least when I did the headers, I stuffed a shop towel into each port - I will be stuffing everything I possibly can into the future!

That's not a bad idea - the negative cable was pretty trashed at the terminal, so I cut it off and redid the end - it seems like it could be a grounding deal since it works great one second and crap the next. Might as well just replace the battery cables to see if that gets me off to the races; at least I know the grounds are good. The starter was the first thing I replaced, and unfortunately it didn't make any difference. I've only had the thing a year and I was always really impressed with how hard it would crank and how fast it would start - until all this nonsense started!

lawsoncl

What's the battery voltage with the engine off? How low does it get while cranking? Looking at your gauge and that everything is dying out, it looks pretty low. How consistent is the problem? Does it happen after it's been sitting, but then restarts okay. A bad battery will get low on capacity or even start self discharging while it sits. The Oreilly's battery test isn't that reliable.

Griffyorcono

Change the battery and return it if that isn't the problem. I'm going with it being the battery cables or a bad ground bolt chassis to battery

BruceB

The issue maybe be the starter and/or the connections from the battery both on the positive and negative. Your dash lights going out when starting are indicating a major draw of battery power. You can remove the starter and have it tested at an auto parts store like Advance, but I imagine they all have the capability. Corrosion of the battery cable hidden below the insulation is also another demon..Also, the negative terminal connection really needs to be clean and tight on the battery. It make look tight, but check it anyway.

Hope this helps

Griffyorcono

https://jeepcables.com/

MaskedMallard

Many many years ago, on a dark & stormy night, I'd pulled into a gas station to get gas. I filled the Renix XJ up & went to start the Jeep. It sounded like a massive power drain & all the instrument cluster gauges pegged & froze. After about 5 minutes, everything went back to normal. I tried to start the Jeep again. Same result, finally after about the 3rd or 4th try, 15-20 later, I started to understand what was happening. I grabbed my jumper cables & connected the black jumper to the negative post on the battery & then the black jumper was grounded to the engine block. Went around & presto, the Jeep cranked & started up. I got to my destination & replaced the large negative grounding cable with a new one. Also, for the fun of it, I got a braided grounding strap & drilled the hole out on one side. I then removed my O2 sensor & bolted the O2 sensor down, with the additional grounding strap cable. I can't remember where I bolted the other end of the O2 grounding strap to, maybe the body? sub-frame?

Best I can figure of what happened that night, was as I was working on my Autocross car (Merkur XR4Ti), and some gremlin(s) migrated from the XR to the XJ.

Thetastycat

Ok well I stand corrected........went to try to figure out how on earth to get one of my multimeter leads on a battery post and the other all the way to the starter to measure voltage drop - and realized that while the negative battery lead, which I've been focusing on, looks good, the positive one on the other hand..........



So as much as I've learned my lesson to not throw parts at a problem, seems like I should just order some of those cables, huh? I do have a winch - is 2 gauge the right call?

ToddPaul

There is an access panel at the bottom of the ax 15, there is five bolts total to drop it. Or you may want to try and put a magnet on a string, drop it in and see what you get . If you slide it along the bell housing it will find bottom. But I would pull inspection panel first and see if you cant fish it out that way.

lawsoncl

Ditto on covering up holes, just remember to remove it so you don't suck it in later. On the CPS, a piece of tape to hold the bolt in the socket helps prevent it from dropping into the hole.

I doubt you have enough slack to cut back to find good copper on that wire. I'd go ahead and upgrade all the rotten battery cables, and bump up a gauge on the starter wire and grounds. I prefer the military style terminals with the post on the side of the clamp to attach the cables, and premade cables with ring connectors on either end. The cheap type of battery connector that clamps onto the stripped wire just lets moisture into the wire and it will eventually rot out again. My local farm-home store usually has a better selection than the auto stores.

Is anyone surprised the Oreilly's guy didn't notice this? Not me.

doublechaz

Parts guy. Generally if he could, he would. He can't, so he sells parts. There are exceptions, and there is also the guy that used to, but now it hurts so he sells parts instead.

Short answer is the parts guy is not a mechanic.

lawsoncl

Yeah, the old timers at the local NAPA are ex-mechanics and know their stuff. The one that really surprised me was the mid-20's girl with tats and a nose ring, who reminded me which headbolt to put the sealer on when I asked for a head gasket. Turns out she had the lifted Cherokee in the parking lot that she rebuilt the engine into a stroker. She refused to let her boyfriend anywhere near it, saying he couldn't be trusted with a screwdriver and the dipsh*t couldn't drive a stick. One of the NAPAs near me has a machine shop, and that guy really knew his stuff too.