Engine/Transmission (1994 - 1998) 12 valve noise

[dodge cummins]

lately i have been hearing a noise upon shutoff on my 96. its not the engine chirp either becuase i no what that sounds like. the noise comes and goes but it only happens as i am shutting off the truck. it sounds like it is coming from the dash area or driver side of motor. it is a whining sound for a split second. the best way i can describe it is that i once had a 85 cadillac deville and the fuel pump used to go bad monthly on that car and when the fuel pump went bad it gave a whining sound that kinda is the same sound i am hearing occasionaly now.

 

[Joseph Donnelly]

Turbo spinning down?

 

[matches]

Not sure but, your truck depending on the year, may have a electric fuel pump, if so maybe thats your noise, need more info on the truck though, does it run good?

 

[dodge cummins]

the truck is a 96 12 valve with a 108,000 miles and runs excellent. the truck is stock except for being straight piped

 

[WDimig]

if you have an open air filter, afe, k&n or whatever, youll hear your turbo wind down when you shut your truck off. i hear mine all the time, i kind of like the noise.



wes

 

[bmoeller]

Same here. Have heard some engines in dozers, that the turbos really sing winding down.

 

[DEZLPWR]

Same here. Have heard some engines in dozers, that the turbos really sing winding down.

You should hear mine winding down on shutoff! I just put in a Dodgezilla 40/35 Hybrid turbo with a 14cm housing, and it sounds like a friggin' 747 spooling down! :-laf You couldn't even hear my stock turbo wind down on shutdown. It sounds cool!

 

[DieselTweaker]

I love the sound of a turbo it's wonderful, Ive got a bad habit of opening the slider on a nice downhill grade and just listening to the turbo, and im sure the people that i pass going up the hill are trying to figure out what plan just went past them :-laf :-laf

 

[bmoeller]

A PDR-40 is a screamer to.

 

[dodge cummins]

i honestly do not think it is the turbo because the noise is coming from the driver side somewhere between the dash and the left side of the motor. plus alot of the times i hear it i was driving around town and my turbo really did not spool up. unlike last night i was flying down the highway and the turbo was working hard and when i shut her off i did not hear the noise. i may be wrong but i do not think they are related.

 

[The patriot]

Maybe one of the doors in the heating/cooling system in the dashboard possibly opening/closing upon loss of vacuum????

I dunno.

Eric

 

[dodge cummins]

thats along the line of what i was thinking of also. maybe a vacuum hose or something, but it seems not to matter if i have the heat or the blower on at all. sometimes i have the noise when i have the blower off

 

[The patriot]

Dont matter that you have it off. The doors inside the heat/ac unit will actuate with the blower off. Even with the heat/ac conrtol on the off position these things can "fail opened", or shut. When the engine is off and no more vacuum, they go to their relaxed position.

I dont even know if this is it, but I've had cars that made the noise you described when shut off.



Plastic control door rubbing against the heat/ac box is my guess. Oo.

I'd bet if you got down under the dash and had someone move the controls to heat, ac, defrost, you'd hear the same thing... . given the truck is running.

Eric

 

[bmoeller]

Could be wrong, but I think the HVAC doors are on the right-hand side of the dash.

 

[MickeysCummins]

I'd say it would be your turbo just spining after Initial shut off, mine does it.

 

[dodge cummins]

ok thanks guys at least i know its not a noise that will leave me stranded one day.

 

[KB0OU]

Could be the turbo spinning down and could be refrigerant noise, mine makes noise when I shut off after using the ac, or had the defrost on, most of the time you have to be in front of the truck to hear the refigerant noise, it is the high side bleeding down. It can also be heard sometimes from the cab and is on the passenger side. I almost allways hear the turbo spool down, ya don't get that nice sound from ricers!!