Engine/Transmission (1994 - 1998) Turbo bark on acceleration?

[johnrv4]

Have you ever heard of a turbo barking on acceleration? Here is what's happening to my friends truck: He has a '96 auto 3500 with a TST 230hp plate, 4" exhaust, and a K&N air cleaner. He has run this set up for about 5K miles with no problems. We were coming back from Muncie, and he said that with a TT in tow and leaving the toll booths, the truck would make a noise that he thought was coming from the transmission when it shifted into OD. I went for a ride with him today, and the noise is coming from what sounds like the air box. At about 20psi of boost, when the truck is shifting into OD, you can hear a "pop" out of the air box, and the boost will drop to 15psi at the same time. The truck continues to run fine without a miss, and the truck completes the shift and is fine. Max boost is about 32psi, and everything looks OK as far as boots and the turbo inlet. When it pops, the boost drops 5psi momentarily, and then jumps back up to 20psi or so. If you hammer the throttle down, the boost will jump to 30 with no noise or problems. Thanks in advance for any advice.

 

[Stranger]

Sounds to me...

like one of the boots is pharting. Tighten all the clamps and try it again.

 

[Air Bulldog]

My truck does the same think and has for year it does it right when it shift if I an steping down on it a little hard.

 

[juicedcummins]

Mine does it also and usually around the 20lb mark on acceleration. It is not a loose boot in my case. I can easily hit 42-43 lbs of boost.

 

[johnrv4]

We checked the boots and they were tight. The truck will make about 32lbs. of boost. It will do it just like you described juicedcummins. I might try to disable the wastegate and see if that makes any difference in the noise. Thanks for the suggestions, keep 'em comingOo.

 

[khaneberg]

I'm not sure if mine is the same as your "bark", but since I removed the snorkle from between the airbox and the fender, when I accelerate hard and fast, at the point of shifting, I can hear ar huffing sound from my air box. Haven't had any problems with it, then again, I haven't been driving it since I am deployed overseas with the Navy. So if it's a problem, I won't know until I get home in October.

 

[illflem]

Found a new one that very well could be your problem just a few weeks ago. Lower intercooler inlet hose had a short split in the seam. At low boost the split stayed closed, no problem, at higher boost it opened up making a whooshing sound. This one was a bugger to track down. Sounded much like the bark from rapid deceleration but was happening instead upon acceleration when the boost was up.

 

[Devildog]

My turbo will "huff" a bit ( or a slow exhale), It happens at the tail end of moderate acceleration when I slowly let off the pedal, say around 45-50 mph.

 

[TEARLS]

I had the same noise at the airbox you are describing,but it went away when I adjusted the governor lever a week ago. Much more bottom end power to.

 

[lpearson]

Same Here

When I put in the TST #10 plate and the DD2's at a certain rmp when it hits OD I get a whoossee/Bark from the turbo/air box. It wasn't there before I did the mods.



What does everyone think about a fix for this? Would a aftermarket air box and filter make a difference? ( I have stock air box with K&N; boot from fender removed. )



Regards,

Lowell

 

[johnrv4]

thanks for the tips

Thanks for all the good ideas. I will try to check it out this weekend. I might just slip my BHAF on it and see how it reacts. I'll let you know what I find out.