I'm very busy at this point in my life with working 50+ hours a week plus 5 night classes at my local university. So I haven't done a whole lot of diagnosing prior to posting this but I hope to get some ideas so during the seconds that I have free, I can pinpoint the problem and get right down to fixing whatever is broken. Thankfully I have a backup vehicle to get me around in the mean time.

On to the problem...


Last night my D (1999 5.9L 4x4) would not start. When I turn the key to the on position, all the dash lights light up, but then when I turn the key to Start position, I hear a couple clicks and then everything goes black. All the lights turn off. Then, after about 10 seconds, the lights all turn back on and the truck seems to be ready to start again. But if I proceed to start the truck again, the same thing happens.

I then had a friend with a V8 Dodge Ram come and try to jump the truck. We attached the cables, and tried to start it. This time the engine slowly turned over but only turned over about 5 times before dying. We let the Ram charge the battery for about 5 minutes and then tried again. This time my truck turned over like normal but it still wouldn't start unless I pressed on the gas pedal. As soon as I released the pedal, it would stall.

After checking the connections to the idle control valve and everything else (MAF, TPS, etc) I tried to start it again without pressing on the pedal and it fired right up and ran like normal (no stumbling or anything out of ordinary).

I drove the truck home and it ran like normal except the Volt gauge on the dash was much higher than normal. Last night it was around 17-18 volts but usually it's at a rock solid 14 volts.

When I got home, I turned off the engine and tried to start it but again, all the dash lights went off and now we're back to square one. In addition, when I went to restart the engine when I got home, a very loud clicking sound from the glove box area started to happen. It was a rapid clicking like an electrical relay. I was frustrated and it was late so I just went inside to bed. This morning when I cam out, it was still clicking so I disconnected the battery and left for work.

I'm tempted to just buy a new battery and start there but I'm not sure that's the best course of action. Could it be a bad alternator or voltage regulator? Could it even be a bad ECU?

 

you DEFINITELY have a bad battery, the question now is whether it too out the alternator with it, i couldnt answer that, if you put a new battery in and it runs fine for a few days and then does dead you also need an alternator, but definitely replace the battery (btw ECU is a ford term, on Dodge vehicles its called a PCM)

 

Loud clicking could be from a bad relay left on. Try taking out a fuse at a time to isolate the clicking, you may need a helper for this. If and when you pull the fuse, you'll know which circuit is draining your battery. Definately change out the battery though. Have the alternator tested cause you're probably running on the juice from the battery and the alt is no charging it and supplying electricity during normal driving.

 

If the alternator wasn't charging, would the volt meter on the dash read 14+ volts while the engine is on?

 

The regulator on the alternator could be bad giving you the high reading

 

14+ volts means the battery is charging. 17-18 volts is WAY to high for an output from the Alternator. Sounds like you could have a alternator going out on you.

Personally, I think you have a bad connection at the battery so clean your connections VERY good. If you have a bad connection it would do everything you stated.

The reason for the stumble is because the battery was soooo low that the PCM wasn't getting a full 12 volts until the battery was done absorbing the energy because of the low voltage. This is normal on a low battery for the motor to stumble and want to die if you take you foot off the gas. When the RPM is up it produces enough voltage to fill the negative gap of the battery and also produce enough voltage to run the PCM. If you loose RPM the voltage output lowers enough that the battery sucks it all and the PCM goes lower than the 12 volts needed and the motor stumbles and dies.

1. First clean all your connections on the battery. Charge the battery fully.

2. Then move to having the battery load tested or replace it.

3. Then move to replacing the alternator (new, no rebuilds).

 

The battery is 4 years old and was a napa cheapy so I'm not going to waste time recharging it and diagnosing it. I bought an Interstate Battery today and will install it tonight. I will then bring the truck to a local Autozone and have them test the alternator.

Over the past year, there has been significant acid (powder) build up on the battery terminals - especially the negative terminal. I did a search and it seems the two primary causes are a bad connection or an over charged battery. Since the volt gauge has always been at 14volts prior to last sunday I'm going to assume it's not over charging but I will still have the alternator checked anyways.

 

Changed the battery to an Interstate Battery. I also changed the negative terminal end since it was badly corroded. Truck now runs perfectly. The volt gauge on the dash reads a hair over 14 volts. I also checked volts with a meter and it read 14.6 volts at idle.

I haven't had the alternator inspected yet but suspect it's fine.

Thanks everyone!

 

It sounds like it's running perfectly.......Another battery bites the dust!