Engine/Transmission (1994 - 1998) Hard Starting - NEED HELP!!!

[95REDRAM]

Hi guys,



I'll make this as short as possible while still giving what I think are the necessary details. About a week ago my 95 started being hard to get running. I first checked the factory manual and and have done enough checks to be confident that the quality of fuel, fuel filter, and injectors are not the problem. This is primarily based on the fact that it runs so good once it does get going.



The truck will start as soon as I turn the key (just as it's done for 7 yrs. & 162,000 mi) but it dies just as quickly. After 2 or 3 tries the oil pressure is up and then I start it by pushing hard on the accelerator while engaging the starter. A gentle push on the accelerator (like is done for cold weather starting) does no good. I have to really lay into it going almost full throttle. On a good day it takes 2 or 3 tries. On a bad day it might take a dozen or more. Once it is running it's just as smooth and has just as much power as ever.



Thinking the problem is air in the fuel lines, I have replaced the two rubber fuel lines (supply and return) between the engine and firewall. I had the return line fail at about 80,000 miles and thought it might be the problem again. Lines showed no visible damage and it did not fix the problem. However, after replacing the two lines I did prime the system via the plunger on the lift pump and it started right up with no movement of the accelerator at all. I'm now thinking maybe it's a problem with the fuel lines going back to the tank but I haven't had a change to check them yet. I know a lot of '94's and 95's had problems with the fuel lines but mine is a very late 95 and I thought the problem was fixed by then.



All help and comments are appreciated. I know something like this never happens at a good time but this is REALLY A BAD TIME for this to happen and I need to get it fixed ASAP.

 

[Joe G.]

All of the 12 valves have the fuel hose problem. You just have to live with it and replace them every so often.



I suspect that you have a overflow valve problem. It's located even with the front injector line on the side of the injection pump between the engine and pump. It looks like a banjo fitting. Before removing it cram a rag in the gap between the engine and pump so the washers don't fall and disappear forever. Don't remove the small hex head screw. Remove the whole valve and take it to your work bench. If it's like the one in my '95 you can take it apart. There is a spring, ball, and a little piece that looks like a derby hat that goes between the spring and the ball. The spring should be . 550" (a tiny bit more than a half inch) with no load on it. You can stretch it and see if that fixes your problem. You may need to replace the valve.

 

[MLee]

starting or not

it sounds like you have tried to cover the bases on the fuel lines, maybe you'll have to check a little further like the electrical connections for the fuel solenoid, maybe, not enough juice is getting through to hold it up to run.

just my penny's worth.



Marv.

 

[esommer2500]

Adding to what MLEE said

if you turn the key to the run position and check the plunger on the bottom of the fuel shut-off solenoid, it should be sucked up into the solenoid. If you can push the plunger arm up, and it clicks and locks in place, this is probably the problem that MLEE was talking about. My '97 did the same thing for about a week, it was getting progressively harder to start. I checked with Cummins and DC and the price for a new solenoid was $288 and $404 respectively. After about a week of turning the key on, opening the hood, pushing up the plunger arm, closing the hood, and starting... it finally quit by itself and haven't had any problems since.



Eric



Oh yeah, this happened about a week after having the AFC housing off to put in the AFC spring. I guess I need to be more careful when moving the solenoid out of the way to get at the pump?

 

[Joe G.]

The solenoid plunger sucks up in the START key position. The run position holds it up.



If the solenoid plunger was not activating in the start key position it won't start. There may be an intermittant problem so that it does not always work. This problem does not sound like that because if there was an intermittant problem it would start ok sometimes and not start at others. Solenoid, possible, but not likely.



Note this symptom:



"However, after replacing the two lines I did prime the system via the plunger on the lift pump and it started right up with no movement of the accelerator at all. "

 

[95REDRAM]

One thing I forgot to mention:



The truck will always (so far at least) start fine just after shutting it off. Let it sit a while and it is hard to start. That makes me think it's related to air getting in the lines or the overflow valve problem as opposed to the solenoid. If this info gives you any new ideas, please respond. Thanks.

 

[Joe G.]

That's consistant with a bad overflow valve. There is a very remote possibilty that it could be the lift pump. Probably not because lift pumps in these 12 valve engines are pretty sturdy gadgets. You should look at the overflow valve as soon as you can. The spring may be broken instead of just weak. Might make you walk.

 

[esommer2500]

I guess I assumed he had already tried to start the truck before checking the plunger on the solenoid. Bad verbage on my part. I stand corrected and bow to the master.



What is the function/purpose of the overflow valve?



Any ideas on what could have caused my solenoid to act the way it did?



Still learning...

 

[RAMSTER21]

Hard Starting

Check your Fuel Shutdown Relay, first before replacing the Relay. It's $42 from Carparts.com. If your solenoid needs replacing contact Peirs Diesel.



Mine was basically doing the same this @ 112,000 miles, the relay was all the problem was, now it start's all the time again.



Good luck

 

[Joe G.]

The overflow valve serves to maintain proper pressure in the injection pump so that it will work right. If the spring or valve is bad it will leak down the pressure into the return line to the fuel filter. This leak down stuff will occur before it affects how it runs. Mine did that. It was running fine and got harder and harder to start.



In this case it may be sucking air from somewhere but I don't see a fuel leak complaint here so the most likely villian is the overflow valve. Every time mine sucked air there was some sort of leak to go along with it.



My truck is also a late '95. Build date 3/14/95.