My truck has started killing after cold starts since the weather got cold enough for the heater grids to cycle. It starts normally, then will suddenly die, sometimes 3 or 4 times, but will always start right back up. It seems to kill when the heaters kick on and after they quit cycling it runs great. Yesterday it even did it after a brief stop when the engine cooled down enough that the heater cycled on. I'm thinking maybe it's a ground problem, maybe the heater grids share a common ground with the lift pump? Any ideas? Also the radio sometimes goes dead while the heaters are cycling and comes back on when the heaters kick off, which is what leads me to suspect ground problems. The truck's a 2001.5 with no mods.

 

Sounds like your batteries can't keep up with the grids. May want to have them load tested.

 

X2 Its always when the weather gets colder, that people are force to do an unwanted battery check. Think of the number of starts the battery has on it not just how long it (or they for us) has been in there. Every time you engage the starter there is a wicked charge that travels along the bottom of the plates in the battery. This results in the plates essentially being fried on every start. Cold weather is unfortunately just when we notice it most.

 

I don't agree with the batteries being a problem, they're a little over a year old and it cranks great immediately after it dies, if the batteries were weak enough that they couldn't keep up with the grids the starter would be dragging. I did disconnect and clean all the battery posts last week, that didn't help.

 

Correction - new 750CCA batteries were installed December 06

 

Those grids pull more load than that starter ever dreamed of. What brand and class are those batteries? Are they class 27? Your alternator only puts out 135 amps, the heater grids pull 190 amps (95amps a piece).

 

I have a remote starter on my 2001 2500 and the past couple of days when I used the remote the engine would start then run for a few seconds and die. then the remote would take over , start the engine and it would do the same thing 2 - 4 times until it stayed running. However i don't think its the batteries either as the engine will turn overjust fine and lites and everything else work fine. I also dont think the heaters draw anywhere near the current that the starter draws . just look at the size of the cables going to the starter and the heaters and you will get the idea. Also the heaters are on longer than the starter is per cycle . I've also been told that these starters can mometarily draw 400 amps or more when you hit the switch. I don't think those heaters draw anywhere near that. So.... tomorrow i intend to start it normally and see if it still does the dying thing. I suppose it will depend on if it is cold enough. Anybody else running across this ????

 

I just went thru this, though mine wasn't dying. I had a 2 year old battery that one cell went bad on. It was enough of an impact that it would make the voltmeter dip very low and the check gauges indicator would light up.

With a good warranty and a bit of a prorate, the new batteries made it all well again. So you probably do have bad batteries. Get a $5 hydrometer at Walmart or a local auto parts store and test each cell. You'll know real fast.

Get some dialectric grease while your there. Clean and coat every exposed surface of all the posts and connectors. It will keep corrosion from building and help make sure you have a very good connection.

 

The heater grids are a continuous load. The starter has a spike at the moment it moves then drops off very sharply after rotating to somewhere around 20 amps. These are 2 very different kinds of electrical loads. They each effect the batteries very differently. If you have a bad cell the batteries will continue to crank to motor. But a continuous heavy load will kill a battery quick.= Massive voltage drop.

 

try running a seperate grounds from the block to the battery, and to the body of the truck and try starting it again, you could use a set of jumper cables to make temperary grounds. Starter circuit is different from the Grids, if there is a poor ground it will try to get to a ground thru other circuits

 

Thanks Nick, I'll try that. I intended to eliminate the quick-disconnect grounds under the passenger battery but haven't yet so maybe there's a loss of ground through one of those connecters although I've inspected them and they look good. The last 2 days it's only killed once so it's very intermittent.

 

Well.... i suppose i had better get a load test done on my batteries before it really get cold. Also..... Is there any reason why you could'nt use deep cycle rv batteries as the main batteries in a diesel pickup ??

 

I don't think deep cycle batteries are designed to deal with the load that the starter and grid heater demand.

 

deep cycle batterys will take lots of cranking and hi-amp use, its just they usually dont hold up well to repeated quick re-charges, they are designed to take a trickle type charge,(low amp over long period of time) In the Canadian Military our LSVW trucks orginally came with a deep cycle batterys, and over a couple of years they were replaced with a normal battery,

Thats why most battery charges has a deep cycle mode, because the deep cycle batterys dont respond well to a normal charge rate

 

Thats good to know Nick. Ok, question, what is different inside between a deep cycle and a automotive use battery? Always wondered.