Help Please!! Why do I hear this sound?

[CRiggan]

With my bullydog downloader on the 90 hp setting and my TST on 4/4 or 4/ anything or 5/4 setting. At around 2800 to 2900 I hear a poping sound like its coming from the intake manifold. It only does this at WOT and with bullydog tow or performance setting and tst at 4/anything 5/anything.



It really sounds like something is popping back though intake. EGT's are in the low 1000's and boost is around 40 to 45 psi.





Any clues?



Truck has 9,000 miles on it 2005

 

[mattymac]

A little more info on the truck would be helpful. Stock turbo? Stock fuel system?

 

[ttreibel]

could it be the turbo barking? are you easing up on the go peddle?

 

[lmills]

do you have a fuel system upgrade??

 

[Prairiedog]

You have no sig so we have little info. If it does it when your auto trans shifts or when you suddenly lift on the throttle then it's probably turbo bark. It's a fairly normal thing, even on some stock trucks but you should avoid it whenever possible as you could eventually bust your turbo shaft.



Scotty

 

[mswift]

I was trying to diagnose this same apparant problem for a friend with an 03. The popping sound occurs almost everytime the auto transmission shifts into overdrive under normal throttle followed by a whooshing sound and a lack of power. The dealer has already replaced the wastegate and the intake side of the turbo and reflashed the ECM. It has gotten bad enough that it split the rubber boost tube leaving the turbo. Does not seem to happen at all under hard acceleration. Anyone have any ideas???



Mark

 

[MCummings]

CRiggan,



Sounds like your truck is cutting out and missing. Depending on your exhaust, you will hear backfiring out the exhaust, or just a muffled thump under the hood.

What is your Fuel Pressure?



mswift,



You are experiancing what is called turbo bark, or compressor surge. This is normal when you put a "chip" on your truck, or turn up the power. A stock truck, only under odd situations will experiance this. Some people have it happen everytime the truck shifts inot O. D. , others never. Alot depends on driving style.

Splitting the rubber boot exiting the turbo was PROBABLY casued by the A/C line rubbing on the boot and tearing it.



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To help us diabgnose your problems better we need to have alot more information about what type of truck, transmission, modifications, and when the problem occurs. Fuel Pressure, EGT, and Boost.





Merrick

 

[mswift]

Thanks for the input. The truck is a completely stock 3500 dually 4x4 with auto transmission. Only modification is an after market K&N air intake. The intake just magnifies the "Barking" that was already there everytime the auto tramsmission shifts to overdrive. Anyone had any luck de-barking these rigs? I wish I could provide more info but this truck does not have any after-market gauges.

 

[Alan Reagan]

If the engine is under load at 2800 rpms, the turbo shouldn't be barking. It sounds like the injectors are misfiring.