Engine/Transmission (1998.5 - 2002) stumble on idle

[odieub]

this is for a buddy of mine 99 3500 five speed start the truck on a cold start just as soom as it start maybe a second or two it will all but die and then run again and the tach will die. it will do this 4 or five times before it stops every 30 seconds or so. then quits and wont do it again till the motor cools down completely. any ideas guys

 

[WrenchRat]

Get a scan tool on it and check for codes. Could be VP time?

Double check your fuel filter. Put a new one in for good measure.

 

[KevinSmith]

Fuel system sucking air? A friend of mine had a 99 that you could check some codes on the dash just like on my 01. I dont know when this feature was started on the trucks GDLCK

 

[rkressg]

Is it temperature specific? I. E. harder to start when it is very cold outside? You could have a problem with the Intake Manifold heater assb.

If you can get a list of codes, it would help.

 

[odieub]

we pulled the codes late last night heres the list P1690 P1693 P0219 P0370 P0336 P0602 P1693 P0500 P1682 it has a hypretec programmer and we pulled the codes with it truck didn't do this when we bought it but doing it now and only on a cold start



found a site that told what the codes were and it looks as if his crank position sensor is failing the rear speed sensor didn't work and we done fixed that. but several of the others seem to revolve around the crank sensor not seeing the same signal as the pump electronics. i think this because the tach in the truck dies when it is doing all of this any body have any other ideas?

 

[MeritBadge]

If you're losing your tach first thing that comes to mind is the CPS (crankshaft) thats where I would start.

 

[odieub]

one other question will a dead crank position sensor cause the truck to not start

 

[jdross440]

I had the cold start problem with mine. I thought it was the VP44 so I took a hair dryer and heated it. Still no start and no codes. I then put the dryer where it would blow down on the CKP and it would start. Replaced it with one from a local parts house and after 3K miles it is failing again when it gets hot. I'm going to Cummins tomorrow to get one.

 

[jdross440]

Got the one from Cummins installed and have been driving it for a week now. It starts and runs good. I took the one back to the local parts house and they gave me my money back on it. The one from Cummins was $54. 69 including tax.