SLOW throttle back-off??

[MCannon]

I have a 06 Laramie..... i gassed er the other day..... and what seemed to be about 10 MINUTES later it started backing off!! What the hell with that???

 

[DBraunig]

have the dealer check the return flow on the injectors, probably has bad injector(s)



Dave

 

[MacHaggis]

If I'm reading right this is your first post. Welcome!



Is this your first diesel?



Asking whether there's a problem with the way your diesel engine ought to be acting, or whether you're expecting it to back off like a gasser (somwething it won't do) when you lift your foot.



If the latter, it's a good chance there isn't a problem.

 

[MCannon]

Yep first post... thanks...

I also have a 91- 12 valve... with a buck forty on her... . Big Mike

 

[RDyson]

Mine does the same thing. If I mat the throttle and let her wind up, it takes a few seconds to start slowing down. Makes you kind of nervous when the stop sign is coming up fast and the engine is still screaming! Driving these trucks has a learning curve to it. Especially a modded one.



Randy

 

[drewRoberts]

sounds normal. . . when you mat it the rail gets highly pressurized, then when you get out of it the CP3 is still pushing for a little, and the only place for that pressure to go is through the injectors. you have higher pressure than what you need so she's still gunna fuel for a bit.



when I'm draggin through town the same thing happens to me and makes it hard to shift into the next gear for some odd reason, however when I hit it right and the fuel is still in the rail. . . HOLY COW

 

[DrDiesel]

What THAT is, would be called Turbo spool. It take`s time for the turbo to spool down and allow the boost to back off. Now you know why all the early twin-turbo Porsche`s have been crash in the first turn... ... ..... :-laf

Turbo`s lag on spool-up and spool-down.

Next time don`t just stab the go pedal and back off. You can cause problems with extreme heat variation this way. 1300 + degrees and then 200 degrees can cause valve seat problems. This IS NOT your ordinary GAS Crap.

It`s a Diesel and you need to learn how to operate it properly.

Sure it`s a work horse, but you can cause damage from improper operation... Happy Motoring... . This Turbo setup is not like your old one. .

 

[DrDiesel]

sounds normal. . . when you mat it the rail gets highly pressurized, then when you get out of it the CP3 is still pushing for a little, and the only place for that pressure to go is through the injectors. you have higher pressure than what you need so she's still gunna fuel for a bit.



when I'm draggin through town the same thing happens to me and makes it hard to shift into the next gear for some odd reason, however when I hit it right and the fuel is still in the rail. . . HOLY COW

Not so... . Sorry..... :{

Higher rail pressure is not the cause. Turbo Spool..... IS

 

[Task125]

Makes driving in the snow and ice intresting

 

[drewRoberts]

excess pressure in the rail has to bleed off somehow and I dont see the CP3 instantly letting go of the pressure. besides if the turbo is still spooling yet there is no fuel going to the fire it is going to slow down if not stall due to lack of back pressure.



boost is made by heat and that heat is made by the pressure of the fuel burning, remove the fuel and you loose your heat source.

 

[LEPage]

I'd also be more inclined to think it is fuel related. I've hated it ever since I picked my 3G up in Sept. '02. If it was the turbo why in the heck is it only on Common Rails? We all know where the turbo pressure goes, back through itself to make the bark that breaks shafts.

 

[snowaholic]

I'm not sure if this will work on the earlier CR's, but if you turn the key to the on position (don't start the truck) and push the fuel to the floor and back 3 times then turn the key back to the off position, it will help to reset the Throttle Position Sensor. Give that a try and see if that helps... ... .

 

[bighammer]

I would be tempted to look into the condition of the go pedal cable just to make sure it's not binding up. Something doesn't sound right.