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jwh21236 08-24-2008 04:42 AM

Electrical and Stall Problem - Please Help...
Hi all,

I recently put all new brakes on my 1999 Wrangler Sahara 4.0L and everything went fine with the install. The Jeep has been sitting for about 4 months though, maybe started 3-4 times, and when I went to start her up, she wouldn't start. I replaced the battery and was able to get it to start, but something isn't right electrically because all of the lights flicker like it's running purely off the battery and the electrical gauge reads 19, pretty much maxs out. It also stalls out when in gear from time to time. My question is...Is this most likely an alternator problem? Or does it have something to do with the IAC or TPS?

Thanks in advance for any help.


rrich 08-24-2008 09:00 AM

Before panicking, clean the battery cables - it may be as simple as that. A bad connection can cause all kinds of goofy things to happen. It could even be inside the battery.

Sitting - could have critters eaten some of the wiring? Look close, they love insulation.

To help discourage rodents, put a few sheets of clothes dryer softener around. They hate the smell. They are good for a few months.

jwh21236 08-24-2008 11:29 AM

Battery Terminals...
Thanks for replying so quick... When I installed the new battery, I thouroughly cleaned the leads off, so I know it's not that. Can the alternator actually cause a gauge to go higher though? That seems weird to me, that's why I'm wondering whether it is something else or not.

Rawkon 08-24-2008 12:00 PM

there is a temp/charging sensor for your battery under the battery tray. the main computer is your actual regulator.. id make sure the temp sensor thingy is plugged in and not messed up. then i would reset my computer your iac/tps wont effect the charge rate. also make sure your battery has a good charge on it. low electricity makes electronics do wierd things

rrich 08-24-2008 12:29 PM

He He - Knowing, wanting, or assuming it's making good contact isn't enough. The symptoms you describe - ACT like a bad connection. It's worth a try and costs nothing.
If that doesn't help, try another battery - no need to buy one, just use one from another vehicle or charge up the old one, the bad connection may be inside it - side terminals are famous for being bad.

Or you can first put in another alternator and ECM for a few hundred bucks, then try it. It's up to you.

jwh21236 08-25-2008 05:20 AM

I definately will re-clean the terminals, but I did use a very stiff wire brush to clean the leads. The battery terminals themselves should be fine since they are brand new right? Now I will admit that the battery did come from Wal-Mart, and maybe something is quite wrong with it because the Jeep wouldn't start and had to be jumped with the new battery??? A friend of mine said that's happen to him and it most likely had just lost charge from sitting on the shelf at Wal-Mart for so long. I will also check the sensor beneath the tray, although I hate having to pull that battery out again, for some reason it's a real pain in the ass.

I won't be able to do anything until Wednesday and I'll report back then, much thanks for the answers.

rrich 08-25-2008 08:55 AM

New doesn't always mean good.
That goes for the battery and the terminals.

You had to jump start the new battery? Right from the start you knew it wasn't right - something wasn't.
Wal Mart batteries are supposed to be fully charged right at the beginning. If it wasn't, obviously something's wrong, you should have stopped there. The higher end of the Wally World batteries are made by John Controls, damn good batteries.

You said it has new terminals - you put on the new ends, not the entire cable? That in itself could be the problem. Those things give lots of trouble.

So there's another possibility - those replacement ends could be at fault. If you are using the side terminal connectors I'd really suspect those. Often they don't sit properly on the battery connection, the insulated lip holds it away.

Even the top terminal kind give trouble. Where the cable end connects to the clamp part - it only contacts part of the cable.

And then of course - the battery - inside where you can't see - the internal strapping sometimes is loose inside.

jwh21236 08-25-2008 11:00 AM

I'm sorry...
What I meant by new terminals was simply the terminals on the battery itself...I didn't change anything on the cable, only really cleaned the ends as best I could with a wire brush. They look completely clean, as in all shiny metal clean, both inside and out. I really don't think it's the connection of the cables to the battery terminals, but I am more and more becoming upset that I had to jump a new battery, who does that? I think I'll take it back and get a different one, and make sure that they test it before I leave. I still have the receipt and it was less than 30 days ago so I'm gonna take it back tomorrow. Is there a specific kind I should get? Or should I get my money back and just go somewhere else?


rrich 08-25-2008 01:12 PM

That pretty much narrows it down. But first I'd have a close look at the terminal connection, just to rule that out for sure.

Wal-Mart batteries, the heavier duty ones, are made by Johnson Controls in Mexico. They are the ones that USED to make the Die Hard years ago (but no longer) - when the Die Hard was the best you could buy.

I don't think you can find better.

You may have a defective one.

The problem is it may test fine on their tester. If they tell you it's fine, YELL!

jwh21236 08-26-2008 06:01 AM

I just thought of something...
If I did get the Jeep started, even by jumping it, wouldn't the alternator take over and keep everything stable electrically, including all lights, radio etc...? If it supposed to, would that mean to have the alternator checked?

jdhallissey 08-26-2008 06:04 AM


Originally Posted by jwh21236 (Post 258418)
If I did get the Jeep started, even by jumping it, wouldn't the alternator take over and keep everything stable electrically, including all lights, radio etc...? If it supposed to, would that mean to have the alternator checked?

Yes that is what is suppose to happen. If you jump it let it run for a few minutes drive it get it above 2 thousand rpm for ten minutes ie down the freeway. It should be fine but if not the first thing I would check is the alternator.

jwh21236 08-26-2008 07:34 AM

The problem was...I got it started by jumping it, then reved the engine continuously to between 1500 and 2000 rpms i guess for about 5 minutes. All of the lights in the vehicle were flickering as I was doing this and the electrical gauge read 19 instead of the usual 14. Then I went to move the vehicle, when I let off the gas, it dropped not only to idle, but it died in gear. That in essence is everything that happened. I had just bought a new battery and installed it so I though maybe it had something to do with that. Now I'm curious as to why it died in gear at all, because even after jumping it, I would think the battery has a little power to keep it idle at least for a few minutes, but it died as soon as I let off the accelerator, no idle whatsoever.

rrich 08-26-2008 12:37 PM

If there's a bad connection to the battery - either outside or inside the battery (thinking about it I suspect it's the negative side) - the alternator cannot charge it properly. It will try, the alternator voltage shoots up and goes out of sight - that's the 19 volts you see. It's trying as hard as it can.
But - the regulator tries to hold that voltage down, so interrmittently it drops the voltage back down again.

No matter how long you try to run it to charge it, with a bad connection it'll never take a charge.

The unstable lights etc - the voltage is bouncing up and down. But you only see close to the peak - as the gauge is dampened - it takes out the fluctuations. Use an undampened analog voltmeter on it - you'll see the radical voltage fluctuations.

It dies when you stop trying to rev it because the alternator voltage drops below about 10 volts, the ECM, the fuel injection, and the ignition shut down at about that voltage. Normally with a battery connected properly the battery supplies the need voltage at idle. Without that help ---.

Putting it in gear loads the engine down slower, the alternator itself cannot supply enough, it dies, same as the above reason.

Try swapping it out with a battery from another vehicle - or put the old one back in.

I have no idea why people resist such a simple thing. When I had my shops I made quite a bit of money on simple things like that - even after I told the customer how he could fix it himself. Go figure!

I suppose it's the "But I don't want it to be that!" syndrome.

My beliefs - diagnose FIRST before throwing expensive parts at it.
New does not always mean good.
And --- KISS!

jwh21236 08-27-2008 05:07 AM

Yay!!!!!! Thanks to everyone who helped me. The problem did infact end up being a defective battery bought from Wal-Mart. I returned it for another one, installed it, and the Jeep starts like a champ. Thanks again for everyone's help, it was very much appreciated.

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