Help!!Wierd engine noise

[Agades]

OK

i had a 99 cummins,5spd

banks power pac

275injectors



when you let off to shift the engine made kind of a fluttering noise

tuff to explain the exact noise

but it did this as soon as I installed the banks



this was two years ago



banks said they had no idea



it doesnt do it if you let off and allow the boost to drop considerably before shifting



I have since traded the pickup and now my dad owns it

it is still doing the same thing

hasn't seemed to hurt anything that I can tell



does anyone know what is causing this?????





Oh yah!! also

every once in a while the pickup will stumble for a split second while going down the road

only once,not repeatably like the shudders that some are having



kind of like you shut the key off for a split second



scares the crap out of ya

 

[Ramboy]

Can't say about the fluttering noise. Probably something with the turbo or air box. The momentary stumble happens to just about all that have an electronic box add-on like the ottomind. Mine has always done it on rare occasions when empty. When towing, it happens at least once a day. I know what you mean; it scares the crap out of you when it happens.

 

[JTBMC]

Check your intercooler rubber connections, my 96 would sound like a woofing of flapping when I let of the fuel and it turned out I had to change the boots it blew off so often that I torn the thing tightening it down

TJ

 

[LSMITH]

The momentary shut-off thing happens to bone stock trucks too, the add on boxes just amplify it. It is scary, and happens to most all 98. 5 and 99 trucks that I know of. It used to bother me pretty bad, but I have since just accepted it. Mine only does it once in a great while though, it has been at least 6 months since the last time. I figure if it has not broken yet it will probably be fine.



If your fluttering noise sounds like a "whoop whoop whoop" getting quieter each "whoop" you are barking the turbo. It is not good for the turbo at all, but then again I have not heard of a stock HX-35 shaft failure either. My turbo gets barked on a regular basis (several times daily), and has from the beginning. Well over 90K miles and it is still going, knock on wood.

 

[Agades]

its not barking the turbo

I ve done that before

its nothing like that

its like the engine is clattering when you let off suddenly

and stops as soon as it returns to idle

 

[Fred Swanson]

Does it sound like valve train noise? Like the valves need to be adjusted.

 

[ACoyle]

Go to Fritz's Ram Tech page and get the full explination. In the meantime, when you get on it hard you are building boost. More boost with a hotter engine. If you get off it in a hurry you have all the intake plumbing and the intercooler pressurized to 30 or so PSI. When you get off it the pressure has to dissipate somewhere. It goes out the intake. I believe Fritz's site says it's not harmful. Look here http://dodgeram.org/tech/dsl/FAQ/turbo_faq.htm



Andy

 

[Michael Hughes]

LSMITH,

I have a 99 with 86,+++ miles on it. It is stock and I have never had it stumble on me. I would like to know if alot of people have this problem?

 

[Agades]

Originally posted by Fred Swanson

Does it sound like valve train noise? Like the valves need to be adjusted.

thats what it sounds like to me



but im not an expert

i was hoping someone knew

none of the other 24 valves ive worked with (5) did anything like this

 

[Fred Swanson]

Agades, has the motor ever been run hot? It could be valve guides. If it is under warranty, take it in, and have them look at it. If it is unquestionably under warranty, Dodge reps will authorize the dealer to pull the head, and have it rebuilt, if need be.

 

[Agades]

never been hot

I bought it new

started making the noise as soon as I installed the banks

to me it sounds like you may be right though



the pump wire has been tapped so I dont know about warranty

75000 miles

dad owns it now

 

[GMcLean]

possibly a slightly bent push rod from idling too long at abase idle when it`s cold out

 

[LSMITH]

Micheal, yes it is pretty common. Most guys I know of with a 98. 5 or a 99 have had the stumble. I don't worry about it at all anymore, it just happens.

 

[MidwestMotorman]

not me

The only time I ever had a stumble was when I had water in the fuel filter canister or when my lift pump was DOA. Letting off of the throttle cuts off fuel into the VP44. Check the fuel pressures. (which should be done regularly with any 24V)



OR just shift at WOT and see if that helps.