Cool, it's not even cold yet, starting problems
 

1996, Dodge, 3500, Cummins, 173,000 miles

When the outside temp drops below 70 F the truck will start and run for a few seconds and than stop. I can do this multiple time for up to 7 or 8 minutes and the truck will finally start and run as normal. If I plug the engine heater in the truck will start the first time and run as normal. The wait to start light comes on for about 3 or 4 seconds before I crank the engine.

I have lost my long time mechanic and have just paid $189.00 for a fuel filter change (OUCH) at Rocky Mountain Cummins here in Grand Junction.

Any ideas? and is this something an amateur should try to fix?

I have done some searching and it does not seem like it could be the grid heater since from what I have read it does not even come on unless the air temp is below 60 F and this problem is happening above that temp.

Thank you for all your help,
Doug

That seems unusual. I really have nothing productive to contribute, mainly because... I'm pretty drunk right now and hesitate to attempt a troubleshoot. One of our more sober fellers should have some ideas shortly.

That all being said, seriously, don't pay anyone else to change that filter. It's easy. Once you've done it a couple times and get a system down, you'll be able to do it in your sleep. It only takes a few minutes. I do it with every service (5K/mi), which is almost five times more often then the service schedule calls for, but I notice my fuel pressure starts dropping after about 4K/mi and that brings it right back. Seriously, even if you buy the filter from Dodge (twice what it costs anywhere else) and pay yourself 50/hr and are slow as crap, you'll still save yourself a hundred bucks. Actually, your '96 may even still have the spin on filter IIRC, which is even easier than the canister nonsense I go through.

*edit: wait, what rpm does it idle at when it's running normally? I've never had it this extreme, but if your idle is too low it will give you crap like this.

yeah could have rolled the o ring or something ... maybe its not tight enough ... :humm:
could also be having an issue with fuel solinoid also ... see that a few times oddly enough only when cold ... the soleniod looses its ability to be a real strong electromagnet when cold for what ever reason .... just a hunch though :humm:

Mine is the opposite, starts perfect every time when it's cold, but once it warms up it will fire up and immediately die and I have to lift the solenoid lever for it to start and run. Really starting to piss me off, actually...

Jbear,
about 800 rpm at idle. I only have the factory tach.
Doug

Well, that should be plenty high enough. Back to the Tequila...

4x4,
Could the block heater effect the soleniod? It starts just fine if the block heater has been plugged in.
Doug

I would think if the block heater was the problem, plugging it in wouldn't be helping the situation. That it does is curious though... anywhere near your temps is still way too warm for it to be required to even help start the truck, never mind be required to start it, which shouldn't be the case anywhere above freezing unless something else is pretty wrong. So I'm thinking something else is pretty wrong.