Dropping RPM's slowly (video)

[joepinder]

As you can see in this video when I am in park or nuetral and rev my engine my RPMs seem to hang for a second and then drop off slowly. I have searched the forums and Ive seen most people say they have a similar issue but it is usually combined with issues while driving like the engine surging while they're driving. I dont have any problems when I'm driving, runs and decelerates fine, it only happens when I rev the engine from idle. Also in these posts I've found most people seem to say that the injectors are causing the problems in these other guy's trucks. Ive think Ive seen one person say it could be a bad torque convertor. I'm personally wondering if it could be a problem with the APPS. What do you guys think? I'm really hoping its not injectors because monies tight right now

[dripley]

I dont see that yours is acting differantly than mine when free revving it. It seems to me when revving that much metal in one direction and you left off the throttle forward momentun is goinng to keep it moving in that direction briefly before the rpm can go down. When I get out off the house today Ill look at mine, but I would be suprised if I see anytging differant. The sheer weight of all the parts you have moving would overcome any resistance in the engine briefly before it could slow down I would think. I am sure some of the more technicly inclined here will straighten me out if I am wrong. The video looks pretty normal.

[Mopar1973Man]

From what I know its the rail pressure spikes high and it takes time at idle rate to consume the rail pressure so each injector is shooting a bit hot of a spray till the rail pressure comes down. You'd see this better if you had a rail pressure gauge.(Educated guess...)

[dripley]

I did not notice your truck is a CR. So that might mine an uneducated guess. It just did not seem out of the ordinary to me.

[packinheat2]

Looks normal to me but I wouldnt want to be free reving it like that all the time.

[joepinder]

Thanks for the input, I posted this on another site as well and all the feedback I got said pretty much the same thing; this is normal. Like I posted on there, I'm used to gassers and on a gasser when I rev the engine and let off the pedal the RPM's drop pretty quickly. No one knew exactly why these trucks do that but the theories were the same as well. They were saying they believe its due to the high pressure that is in the CR which really makes sense, pressures gotta go somewhere. I'm new to Diesels and this truck is new to me so I am nit-picking every little thing that seems ununsual or different to me. I'll calm down after a while and stop being so overly worried once I get to know the truck and the engine better.

[AH64ID]

The CR's are slower to come down in rpms in free rev, its partially the nature of the pressure and partially ECM programming. When it hangs up is when injectors are suspect.