This is my first post/question on this forum. I have been lurking for a while now and learning more about my cummins Dodge has been great.

This evening when I got in my truck it seemed to drag a little when I started it. Normally I just have to bump the ignition and it starts. Then while driving the headlights and the dashlights would get dimmer and after a few seconds get bright again. This went on for a few minutes until I got to where I was going and turned off the engine. When I got back in the truck and started it, it did not seem to drag when starting and the dimming and brightening of the headlights and dashlights did not happen.

Any suggestions/ideas on what could have been causing the problem? Battery, alternator, voltage regulator?

My first thought was the battery. The truck is not a daily driver and I drive it mainly on the weekends.


Thanks

wtxbadger

 

what was the temperature outside?

It sounds like the grid heaters doing their thing.

Welcome to the site, fill out your signature under User CP so we can see what you have for a truck.

 

Do the obvious first.

Remove, dis-assemble, and CLEAN both cable-ends.

Clean the battery posts.

Take loose and CLEAN both cables at the starter and ground, both the contact points and the cable-lugs.

On the HOT cable, there is a less-fat cable, about finger-diameter.

About six inches along this cable is a plug/dis-connect; dis-assemble and CLEAN both portions of this plug.

Locate and clean the various ground points under the hood; there are not nearly enough and the wire gauge is pretty stingy.

Doing this maintenance will narrow down the search, should the problem re-occur.

 

yep, my truck does that all the time when its cold out, normal thing for them, watch your voltmeter, it will jump back and forth on you.

 

the grid heater is like a toaster over coil on the intake path... when it is below 60* out they will cycle until the truck warms up. that is what the "wait to start" light is indicating. It heats the air that goes into the cylinder to aid in combustion. just be carful if you take a lot of short trips in the cold, when they cycle they will pull the battery down some, it will need time to build back up.

 

maybe its the time of year for the "why do my headlights dim" thread again...
first sign of winter arriving, kinda like the leaves changing....

 

Thanks for the advice.

I will update my signature. I have a 1993 D250 with 166,000 miles. It was a one owner truck and the previous owner followed the maintenance schedule to the letter. He kept a notebook that logged every time he filled up. mpg, and all maintenance that was done.

The grid heater turning on and off would seem to make sense. It was around fifty degrees yesterday evening when this happened.

Guess I should have done a little more checking on previous posts. I will check out the electrical connections under the hood this weekend. They look okay when I have the hood up, and did not see any obvious corrosion on the terminals but it is worth re-checking.


Thanks

wtxbadger

 

You can also just un-hook the power to the grid-heaters, right at the battery, and not be bothered with the mess.

They are the two identicle semi-fat wires, with ring-terminals, that are piggy-backed on the hot battery cable end.

They are on there for cold-start emissions, more so than starting assist.

I have them dis-connected on all four of our Cummins trucks, with no adverse effects.

 

I just got my grids working. On my truck, they do make a difference in starting. Trying to start in the cold without them, the truck spits and sputters like I have a heavy cam in it or something. With the grids, it fires up better, but still needs to get up to temp before taking off. JMO

What part of the country are you in wtxbadger?

 

Wow, mine did that yesterday and I didn't know why. Now it makes sense.

Thanks guys.

 

I am in Midland, Texas GIT-R-DONE.

 

You shouldnt have much trouble down there with needing the grids. I know a few times a year it gets cold, but not a consistant deep freeze that many receive up north.

 

If your grids took your battery down enough to slow the starter, that might be a sign its on its way out.

 

That was definitely one of my concerns feveree40. I have not found anything on the battery that shows how old it is. I would imagine the grid heaters draw a good bit, but it seemed to me that between a good battery and an alternator that is fully functional I would not see the headlights and dashlights dim when the grid cycles on.
I have not tested either one and may be speaking out of turn with a limited amount of experience, just now getting into owning a Dodge diesel, but would think if the owners of these trucks when they were purchased new had experienced this, there would have been quite a flap about it considering the money they paid for their trucks. Just a thought based on limited knowledge and experience.

Thanks

 

The grid heaters draw 220 amps. The stock/OEM alternator is rated at a maximum output of 120 amps.

That's why Dodge specs an 800 CCA (@ 0*F) / 1,025 CA (@ 32*F) battery for our trucks.