Hard to Start in Morning ( 1st Cold Start)

[Murphy67]

As the temperatures finally started dropping I've had a hard time getting this truck to start. Symptoms: Engine (pops off) immediately then dies. It is not possible to stay on the starter because the s-motor is thrown out immediately when engine tries to fire up. Now at about 20 deg. ambient air temp. it is taking 3-5 key cycles to start. This is a new problem, as my old stomping grounds were in Denver, Co. and I usually did not have the truck plugged into AC.



Question:



Owner's Manual Cold Start Procedure calls for full depress of accelerator prior to cranking. Does this setup the pump for extra fueling at cold start? If so, how can I tell if this is functioning?



Second thought is that the heaters are not functioning properly. Engine “wait” does illuminate, but it seems rather short but I’ve not timed it yet. Also, I have noticed there is no Post-heat cycling.



Another symptom cropping up at the same time is deceleration. I don't know exactly how to explain it but when letting up on the throttle, the speed drops down and has a little bump, or recovery at idle. It is worse at cold verses hot engine temperature. It doesn't seem to matter if revving it just a touch or allot.

 

[illflem]

Sounds like your intake manifold temperature sensor isn't functioning correctly. Could be as simple as a bad wire connection or dirty sensor from an over oiled K&N filter or as serious as a bad PCM. The Dodge service manual has a chart of the sensor resistances at various temps. If you plug in do you you have the same throttle problems? What year is your truck?

 

[Cummins Corvette]

I don't no about the rest of that stuff, but ya push the throttle down before starting to set the choke. Maybe try pumping it a few times, that seems to help on mine. The accelerator pump squirts a little fuel down the venturis and makes it start a bit easier.

 

[Murphy67]

RE:

illflem,



I agree with the air sensor repost, as I have just broken open the book to the resistance values. I don’t know about a change in the deceleration problem using block heater but if I were to assume, it would not change, as the symptoms still exist after full warm up. Idle was low after piers gov kit installed but worked fine for thousands of miles. Reset to 800, best guess with no change in symptoms.

 

[Timinator]

Mine doesn't have a choke or venturis. Those are for carburetors. I have an injector pump though.

 

[Cummins Corvette]

What? No carb on yours?

 

[rubberneck]

Originally posted by CAnderson

I don't no about the rest of that stuff, but ya push the throttle down before starting to set the choke. Maybe try pumping it a few times, that seems to help on mine. The accelerator pump squirts a little fuel down the venturis and makes it start a bit easier.

probably a bad spark plug or maybe plug wire. wait a minute i know the glow plugs

 

[Cummins Corvette]

All these problems with the carb on my ram makes me wish the people at cummins would put fuel injection on these engines!!

 

[LarryB]

Originally posted by Murphy67

As the temperatures finally started dropping I've had a hard time getting this truck to start. Symptoms: Engine (pops off) immediately then dies. It is not possible to stay on the starter because the s-motor is thrown out immediately when engine tries to fire up. Now at about 20 deg. ambient air temp. it is taking 3-5 key cycles to start.

Could it be a bad relay in the "hold open" circuit for the fuel shut-off solenoid? The "pull open" circuit works when cranking but the "hold open" may be too week to hold when you let off the key causing the engine to die. After the relay or solenoid warms from a few tries it holds.



Ahh, a shot in the dark.

Larry

 

[Strick-9]

Murphy67,



I've been battling the same problems for a while. Three days ago, my truck took 6 attempts to start. Exact same symptoms as you describe. Engine fires right off on first revolution just enough to kick the starter out then dies. I tried various amounts of throttle and nothing helped.



I'm running one battery and I didn't notice that it was turning over slowly at all. But I found a loose battery clamp, a loose wire in the clamp, and the starter wire was also loose.



Once I tightened everything back up she fires right off in the morning. The slower starting happened over several months and it was so gradual I didn't notice it.



Your governor is causing the poor return to idle that you described. Who did the install? Do you have stock idle springs? Do you have the flat bottomed seats? Did you measure stud length on the install?



When the governor kit was installed, how was the idle? You mentioned that it was lower after the install, but was the idle too high and the idle speed lowered too much or did the spring installation alone cause the idle to drop?



Too much spring preload or stiffer idle springs cause the idle to be weak and not recover well. But it also causes the idle to go up not down. So I need a little more information.



-Chris

 

[Cooker]

I have the same problem. If I forget to plug the truck in and temp is less than 30, it will fire and then die. If I give it a little throttle it will continue to run. After a few seconds it will run on it's own ok.



Although I am not overly concerned about this, I would like to get to the bottom of it.



Once it stops snowing, I'll clean the bat. cables and make sure all connections are tight. It just doesn't seem like that will solve the problem.

 

[Jeff H]

Pumping does nothing

It was 10 degrees today when I started mine. Forget pumping the pedal. After the wait to start goes off. I push the pedal in 1/4 to 1/2 way down. Hit the key and you may have to hold the key for a few secounds till she can stay running on its own. It does run really rough for the first few secounds too. Don't worry about flooding it. You can crank all day and it won't flood.

In negative temps I cycle the intake heater twice before starting. That really helps.

 

[Hummin Cummins]

Seems to be a cummins trait, always seem to be really cold blooded. That is if you are sure your heater is functioning properly. I had a 400 in a freightliner once better have it plugged in under 40. Wont idle by itself for about 30 seconds, just hold light throttle for a few seconds it wont be so rough then she'll idle just fine

 

[Cooker]

You think a Cummins is cold blooded. You should be around when some mis-informed (read: should have bought a Cummins) guy is trying to start his PowerJoke is below freezing temps.

 

[PZicha]

Murphy67..... I had the same problem somewhat , all it took was to raise the idle by about 100rpm / starts like a dream now even in sub zero weather

 

[Jeff Burke]

I am also experiencing the same starting problem this year. Last year I had no problem starting. I have added a set of 370's this year, and soon after that, I noticed the truck did not start as well as before the injectors. Has anyone else seen this?

 

[GMcLean]

a few good ideas have been suggested here that are likely a good part of your problem. . Check idle, if too low it will start and die. try putting the weight of your foot on accellerator pedal, if fires, adjustidle screw at back of pump. Try having someone watch the fuel shuttoff solenoid on start up in the morning, if it is slow to pull up or pulls up and drops, you likely have low voltage at the pull in or hold in windings and cleaning the battery cables may help(don`t forget to clean the connectors on the drivers side battery possitive stud for this is where the relay gets its power)

the old style fuel shut off solenoids did not have a ball at the shut off lever and were prone to rusting slightly or binding on pull up and can burn out the solenoid. lubing the end or replacement of the solenoid with proper adjustmentcan help.

if it feels like the fuel is draining back to the tank, check the fuel return hose at the back of the fuel inj pump above the lift pump, it may be starting to rupture and allow air into the system, another couple of places to check are the fuel heater/stainer electrical connector for signs of burning or wetness on the plug from diesel, or behind the plungger boot of the lift pump. .

By the way did you check the pre-heaters for pwr at key on when cold?? (below 56 deg)

 

[carson6]

start's *****en

Mine start's fine @ 20 not plugged in and only one "wait to start" cycle and not touching the peddle. idle is 900 when warm(500 when cold)

 

[ADSmith]

I have also had cold start problems three different times. Once, it was low fuel pressure caused by the fuel return valve getting weak. The other two times, it was caused by the wire going from the grid heater solenoids to the heaters themselves. It appears the vibration from the engine broke the wire in two where it was wire-tied under the injection pump. I have replaced both of the wires and routed them differently so I have no wire ties, and it starts great now, even in single digit temps when not plugged in.

 

[Dennis Garrett]

It hasn't been below 30 here for the last few days, but I think mine's doing better since i tightened up the nuts on the two relays on the fender well, under the driver's side battery. I read a post here about loose nuts, and found all 4 of them were only finger tight. They are under rubber caps, and easy to get too, takes a 1/2" wrench or socket.