Throttle required to start

[Thessgtcronin]

Jumped in the rig (1996 2500, A/T, 2wd) and the truck had a really lazy slow crank like the batteries were dead. Batteries tested "good", new fuel filter, new lift pump. Truck just slowly cranks unless you push the throttle a fraction of an inch. Puff of black smoke and presto, she's running. Idles smoothly, runs solid in town and on highway. Anyone else have the same issue? I've read that these p-pumps were designed to be started at open throttle, but I never used to have to do this. Truck is stock, no mods. Thanks for the time.

[Dieselfuture]

Slow cranking with good batteries could be, weak starter may need contact plunger kit, or brushes could be loose battery cables and dirty grounds. As for applying some throttle on start up, it does help to start quicker. When I had my 12 valve I used to do that too, but also you might want to check the fuel solenoid for sticking. They get old and rubber boot falls apart then moisture gets in and rust them up

[Mopar1973Man]

Starter most likely. I've seen where one brush fails and the starter is now on half power and struggles to twist. Contacts typically just don't deliver power yeah it does happen that it could cause poor cranking but rare. Another is cables I've seen some battery cable that look like junk and people do weird things to gain a better connection.  

[BIG-BLACK-DODGE]

I have a 98 12 valve and it cranks a few times then fires but if I touch the throttle just a hair it fires instantly.

 

I have heard of slow cranks like that happening because of timing being moved. 

Might want to look into that.

Previous owner had the KDP done and front cover all sealed up so maybe the shop that did the work bumped up the timing? This 12 valve barely smokes but pulls way harder than my 24 vslve did on level 5 with the Edge. 

 

[98whitelightnin]

I’ve never been around a p-pumped truck with manual trans that didn’t need a touch of throttle to pop off. My 95 auto never needed extra fuel to start.

[Mopar1973Man]

25 minutes ago, 98whitelightnin said:

I’ve never been around a p-pumped truck with manual trans that didn’t need a touch of throttle to pop off. My 95 auto never needed extra fuel to start.

 

Even Auto's require throttle in cold weather on the first start to fire up.

[Guest 04Mach1]

The Dodge instructions on the driver's side visor of my 97 auto instruct to depress throttle 1/4 of the way before cranking. My 97 cranks alot longer if I don't depress throttle. It fires instantly if I apply just a little throttle.

[BigBen]

On 6/8/2018 at 1:06 PM, Thessgtcronin said:

Jumped in the rig (1996 2500, A/T, 2wd) and the truck had a really lazy slow crank like the batteries were dead. Batteries tested "good", new fuel filter, new lift pump. Truck just slowly cranks unless you push the throttle a fraction of an inch. Puff of black smoke and presto, she's running. Idles smoothly, runs solid in town and on highway. Anyone else have the same issue? I've read that these p-pumps were designed to be started at open throttle, but I never used to have to do this. Truck is stock, no mods. Thanks for the time.

You should not have to give the truck any extra throttle to start! The only time i need to give any extra throttlw is when the ? drops below 0*F and I forget to plug the truck in! If your idle RPM is below 700 then you need to adjust the idle screw on the back of the pump. Its a 10mm bolt that limits the backwaed travel of the throttle linkage. Its hard to see and a pain to get a wrench on. Start the truck and adjust the screw until you have between 700-800rpm, Cummins spec is 750 for most B series engines. If your idle rpm is already within spec then there are number of other things that could be causing a hard start. As previously mentioned the starter could be on its way out and if your cranking RPM is below 150 I would defintily go after that. If you still have problems after that things get a little more involved. 

[Mopar1973Man]

Just done the same thing on an 1997 Dodge 2500 in Brogan, OR so the owner didn't have to hold the throttle and/or plug in on cold mornings.