I hope some of you can help me out here. I've done lots of searching on these issues, but I haven't found any hard answers. I've found a few matching issues, but nothing that ties it all together. My truck is a '99 Durango, 5.2L. I don't have a remote start, but there may have been one before I bought the truck. There are still parts of an aftermarket alarm in the truck even though the truck doesn't have an alarm. Here's what happened to my Durango:

One morning, my wife got in the truck and the battery was completely dead. The truck wouldn't start, the power door locks wouldn't work and the lights wouldn't turn on. So, later that evening, I attached jumper cables and tried to start it. The truck would start, but would turn off right away. I had to press the gas and hold the rpm's in order for it to stay on. After holding it for a short while, I let go and it stayed on. I started checking the windows, radio and wipers and everything seemed to be working. I then turned the truck off and checked the battery connections. There was some corrosion on the terminals so I cleaned it off. I tried to
start the truck again and the battery was dead.

So, I took the battery to Autozone and they charged it for about an hour. They told me the battery was good. I put the battery back on and started the truck. I had to press the gas again to keep the truck on. While the truck was running, I disconnected the negative terminal from the battery to see if the truck would keep running (I've since read on some other posts that this might be bad for my truck). The truck stayed on so I reconnected the battery.

Now I went to go turn the truck off. I turned the key to the off position and the engine was still running. I switched back and forth from the on position to the off position several times and eventually the engine turned off.

I then decided to take the alternator off and get it checked out. Autozone said my alternator was fine. I put it back on and again I had the same issues (press the gas to start the engine, mess around with the key to get the engine to shut off). I wanted to tackle one problem at a time and I thought the ignition switch was bad. I bought a new one and installed it. When I went to start it, the battery was dead again, so I had to attach jumper cables to get it started. After getting it started, I let the engine run for a little while. I tried turning the engine off and back on; this time the engine started normally. It seemed that I only had to press the gas for a cold start. I also didn't have to mess with the key to turn it off.

I then disconnected the negative from the battery and checked out the PCM. I pullled the plugs and they looked fine. I then looked at all the fuses and they were fine. After reconnecting the battery, the truck started up normally. I tried turning the truck on and off several more times and the problem with the key in the off position while the engine was running came back.

I apologize for the long description, but didn't know how else to do this. To break it down, here's what I know:
- If I leave the battery connected, it'll get drained.
- If the truck sits for a half hour or more, then I have to press and hold the gas to get the engine to stay on.
- If the engine has been running and I turn off the truck, then I can start the truck normally.
- When I turn the key to the off position, sometimes the accessories will turn off, but the engine will keep running.
- Autozone says I have a good battery and a good alternator.
- I've installed a new ignition switch.
- While the negative post was disconnected, I pulled the plugs from the PCM and put them back on.
- While the negative post was disconnected from the battery, I turned the key in the ignition to the on position and waited 30 seconds (to reset the PCM).
- I've checked all the fuses in the engine fuse panel and in the compartment fuse panel ( I don't know how to check if relays are good).

Based on this description, does anyone think I've got a bad powertrain control module (PCM) and/or central timer module (CTM)? Is there a way to have these checked out to find out if they are good. If it's not these modules, what could be causing these problems? How much of my problems were caused by doing the old schoold alternator test? Please help! I've prided myself on staying away from dealers for any auto repair. But, I need some big time help on this one.

 

Cisnerca,

Welcome to the forums. I would speculate it may be the PCM module as this problem is intermittent. I would also check for that big 140 amp fuse as alot of 99 durango users had issues with engines stalling and the big fuse was the problem.

 

Kensai, could that main fuse be intact but bad? I'm assuming it's not blown since I can start the truck.

 

Yes, it is the main fuse. Do a search for something like durango cannot start or trouble maintaining idle. Found it was the main 140 fuse that was bad. This issue was reported mainly by the 99 durango owners.

 

Thanks, I'll pull the fuse out and inspect it tonight.

 

it almost sounds to me like you have a short in the electrical system (or most likely something is drawing power all the time) this would kill the battery, with a dead battery the truck will not idle correctly (the PCM is very picky about battery voltage being just right in these rigs for some reason) but when you hold the rpms up it gets enough juice from the alternator to keep the truck running, and put some juice back in the battery (hence why when you left it running you could turn it off and start it back up immediately but not if you waited a while), and based on the cost of the PCM i would start looking for stuff that is staying on when you turn the truck off that would drain the battery

another thing could be the IAC motor on the back of the throttle body(causes the engine to not start unless you are holding the gas, and makes it difficult to maintain idle until it "finds" the home position), but that should not kill the battery, unless there is a short in the motor which is another LESS expensive part to replace than the PCM

HTH shrps

 

Hey, shrpshtr325, thanks for the input. I'll start looking for something that might still be on after the truck is turned off. Is there a way to check if the IAC valve (motor) is good?

 

Update. Well, either I have no idea what I'm doing, or something's really wrong. I had the truck running for a while to get the battery charged up. I turned off the truck and attached a short wire to the positive terminal of the battery and a 20 amp fuse to the other end of the wire. I then set my new multimeter to 20A DC and connected the leads to COM and 20A. I held the black lead to the negative terminal and the red lead to the other side of the fuse and the fuse on the wire blew. So, I pulled a fuse from the engine fuse block, wired in a new 20A fuse, and tried my multimeter again; the 20A fuse on the wire blew again. Unfortunately, I inadvertently wired in a 30A fuse for my third attempt. When I connected the leads, my multimeter blew an internal fuse and was possibly fried. No more testing tonight - have to get my multimeter fixed.

I was testing the load on the battery correctly wasn't I? Since the truck was off, there should have been well under 20 amps. Since I couldn't do anymore electrical testing, I checked out the fuses in the engine fuse block and they were all okay (including the 140A main). I then also disconnected the plugs from the old alarm brain box.

 

Well, I went to get something from the truck this morning before going to work and I noticed that the interior lights were still on. So, I tried starting the truck and it turned on normally and turned off normally. I guess that stupid alarm box was draining the battery and causing all the problems. I'll check it again tonight when I get home to see if the battery is still charged.

 

To me, this still sounds like it could be the alternator. How does autozone check the alternator?? Last year my truck would freak out when the alternator went out.. i would have to hold the gas to start it and to keep in running. It would also help alot to make sure your battery terminals are free of corrosion. but it still could be the aftermarket alarm system. good luck