Archived Very hard to start Help!!

[st louis assembly]

My truck is a 96 4x4 auto with 87K miles. Problem first surfaced a week ago, then a few days ago, yesterday and again today. Temps have been around 55-65 . Was hard to get going today even with the truck plugged in and block warm. You crank the starter and it seems as if it is getting no fuel. crank again and same thing. after a little while it may decide to fire a little and then smooth out after 30 sec of reluctant running. The batterys are 54 months on 60 month batterys and test good to fair on charge, the fuel shutoff solenoid is working on crank and stop, no leakage from the fuel lift pump weep hole. once it gets running it runs fine as always so fuel flow must be OK unless something is poor at start. I haven't noticed lately but am going to test the air intake heaters for operation in pre and post cycles . Would they really be much of a factor at 55 degrees??



The service manual lists many things that could cause hard starting. Where else can I look easily before I take it to the dealer or cummins/

 

[Joe G.]

Do you have a fuel pressure gauge? If so, what do your fuel pressures look like?

 

[KB0OU]

Check the fuel hoses, probably have some leaks, may not leak fuel but they let air in and you are having a hard time starting until the air is pumped out, check fuel supply and return to fuel tank.

 

[MCummings]

This is a classic.



'96 with ~100+ miles and it's 8 years old?



Your rubber return lines have taken a dirt nap.



They won't leak,, but when you shut the truck off they will suck in air, causing a Hard start condition.



The situation you describe is exactly what a truck feels/sounds like right after an injector swap/install and you have to purge the air out the lines...





I would try a search in teh 12V forum for "Return lines" or "Rubber return lines"



HTH,

Merrick

 

[Gene Arnold]

I had the same problem with my '96 when it had the same miles on it. It was the return line. I had Cummins Intermountain do the replacement (these old hands can't reach where they once did ). To verify that this is your problem, try using the manual pump (a lot of strokes required) to assure you have fuel for a quick start. Mine would start normally when I did this.

 

[CarlJensen]

My 95 was an overflow valve. I checked this first because it is easy to do. If you have the unit that comes apart the spring should be . 5 inches, try pulling it a little longer. What has been said about air leak is right on the money, you are picking up air from somewhere. The book gives you the list to check but overflow valve and leaking return line are the two most common. By the way, any lines replace should be marine grade from a marine parts house. Will last a whole lot longer. 5/16 return size and 3/8 supply. Good luck.

 

[st louis assembly]

thanks for the help on hard to start My old hands won't do the job either.

I had the same problem with my '96 when it had the same miles on it. It was the return line. I had Cummins Intermountain do the replacement (these old hands can't reach where they once did ). To verify that this is your problem, try using the manual pump (a lot of strokes required) to assure you have fuel for a quick start. Mine would start normally when I did this.

My old hands won't do the job either. Guess I had better open the wallet for this one. I think I will have Gateway cummins do the work rather than a Dodge dealer.

 

[st louis assembly]

solution to hard to start

I had Gateway Cummins find and fix the problem. They replaced the fuel pump which was not building enough pressure but the hard to start problem remained for them the next morning. They found that the injector pump anti drain back valve was defective so it was changed out. It started fine the next morning and has been doing fine. I can't find out where the injector pump drain back valve was that they replaced. Anyone have any ideas??

 

[Joe G.]

That's the overflow valve. It is on the engine side of the injection pump and looks like a banjo fitting. It was what was causeing the hard start. The lift pump was probably ok.

 

[st louis assembly]

end of story

The truck is running fine now. The fuel pump replacement by cummins was ok by me and the relief valve work did the job. Only problem was that when I picked it up I had an ABS warning light on and no vacuum pressure. Easy to fix on the spot. They had left a vacuum line apart and that fixed it all. The fuel lines started to really leak withen 2 days of the pump replacement so I had Dodge check them out. The replaced both lines around the auro trans area and believe me they were in bad shape. I think that the new pump pressure thru the anti drain back valve then was letting fuel to return to the tank under higher pressure so as to cause the return line to really give way. Only problem driving home from Dodge was that the engine temp would not work. Another return. They had pulled the wire out of the sensor plug getting hands into the tight spot for the fuel line work. They took care of it an all is well. Really wish Dodge would build this truck so that hood and fenders rotated forward for easy service. There is just no room for hands and tools to do much of anything on the side of the engine easily or without messing something else up. I think any of you guys that have the patience, tools and skill to do fuel pump ,filter, and fuel line work without leaving too much blood and being able to keep your blood pressure down are remarkable.