Engine/Transmission (1998.5 - 2002) 2001 Proper Start Sequence

[DBardeen]

My 2001 starting sequence has changed. Just recently when turning the key to the "Run" postion prior to starting the engine the lift pump no longer operates. The grid heaters operate, the wait to start light cycles as it should, but no lift pump. The engine starts fine by just turning the key. Any ideas?



I have a fuel pressure gauge in the truck and it reads zero until you bump the starter then the pump pressures right up to 13 lbs. Changed batteries to Optima red tops several weeks back, but not sure why that would cause this.



Oh, the truck also has remote start.

 

[BOstiguy]

That's exactly how my 01' starts, my lift pump has never started without bumping or actually starting. Is it a factory fuel system?

 

[16919]

I would check your lp. It is supposed to cycle before the truck runs to prime the IP. The injection pump alone will draw fuel for a while but will eventually crap out. Where is your guage at? Better safe than sorry. My . 02

 

[DBardeen]

Factory fuel system. My gauge is at 13 psi.

 

[DMcLeod]

Has the ecm been reflashed? I believe the latest software shortened the lp run time before the starter is engaged. You should hear the lp kick on momentarily when you turn the key to the on position.



On my 01, the lp originally ran 2sec (I think) whenever I turned the key on before engaging the starter. After the 2sec, the pressure would drop to zero. About a year ago, the dealer enabled the high idle feature and I believe it required a software update (if I remember correctly). Anyhow, now, when I turn the key, the lp runs for a very short time - and acts like you describe. I can see a wiggle on the pressure gauge, but the lp doesn't run long enough to give you a full 13psi or whatever. If I can recall correctly, the change had something to do with easier starts on some trucks.

 

[JR2]

I don't think you have a problem, your truck starts fine, runs fine so its fine. My truck acts the same as yours.

 

[P Pacatang]

My lift pump does not run with the key in the on position. Only when you bump the starter it runs. It has never given me any problems starting in the mornings.

 

[tabell]

On my 99 you have to bump the starter to get the lp to run. You are fine.

 

[SAronson]

My 98. 5 will run the LP sometimes and not run it other times when the key is turned to "on". When I bump the starter it "usually" runs the LP for the 25 sec. cycle, but not allways (the other times it runs for a few secs. then stops). What gives the LP it's signal to run? I know it's supposed to have two operation modes, but where do these signals come from? I relocated (big line/ Vulcan) and replaced my LP 4000 miles ago, and it was fine/ normal until about 1000 miles ago. I'm thinking this is an electrical problem and not a LP (mechanical) problem.



DBardeen... . if your LP used to cycle in the run position and now it does not (somewhat like mine), then something has changed. I have checked all connections/ grounds and all is good. I'm wondering if the FCM on the VP is to blame for these bad signals to the LP.....

 

[AlFischer]

My 2201 runs briefly when key is first turned on. If starter is bumped runs for 25 seconds. If started and let idle seems to cycle. (I can hear it plainly since it is on frame with no rubber isolator YET)

 

[Bob Cochran]

Mone acts just like Al Fischer said above.