Turbo Hissstststsssss...Noise?????

[over200]

Alright this is the deal, On hard acceleration when it shifts from 2nd to 3rd their is a very distinct Hissing sound really a hiss skipping noise!! Has anyone heard this before???.What is the problem???? What do I do to fix it???
This is a 2000 f350 7.3 4x4.

Thanks,
Howard

[purduefarmboy460]

Sounds like you are just dumping boost between shifts, nothing to worry about I don't think. Someone outta have a more in depth response soon!

[over200]

It actually sounds more like it is loosing some boost like it is spitting it out cause something cannot hold all of the boost or maybe Bleeding is a better word?? Im not sure although this spitting sound does not reflect on the gauge!! I know when the truck was newer it did not make this noise....The sound is very distinct and can without question be heard by anyone in the cab....The sound is the cross between a hissing cat and a rattlesnake!! I don't know how else to describe it??????...One of you Diesel guru's can surely solve this prob for me comon Guy's!!!!!!


Howard

[purduefarmboy460]

Mine does the same thing, I don't notice a drop in boost, rather it holds off until the shift it somplete and then builds on up to 20+

Do you have any mods done? Wastegate un plugged or anything?

Someone else outta be around shortly

[mattyz]

I've heard a noise like that when your rad cap is releaving pressure because the head gaskets are leaking compression into the coolant system.

[wesjones]

i agree with farmboy...it sounds like boost pressure. do you have and auto or manual. if auto...do you think its shifting late? or, do you think it only makes this noise when you accelerate slowly and the trans shifts late naturally?

thats what i can tell you...

wes

[over200]

Originally Posted by purduefarmboy460

Mine does the same thing, I don't notice a drop in boost, rather it holds off until the shift it somplete and then builds on up to 20+

Do you have any mods done? Wastegate un plugged or anything?

Someone else outta be around shortly

Yes, I have a Diablo chip, Quickie pedal, Valve body in tranny, air force one induction system. I don't have the wastegate unplugged and the truck didn't always do this only since the motor has got higher mileage on it and it only does it on hard acceleration! Driving the truck normally everything sounds right!! Because of the air induction you can really Hear the air sucking through from inside the cab! I Hope it's nothing serious as the other reply above scares me!!!!

[Cyclist 06]

don't worry about it, it's normal. My 06 does it and it gets louder with each mod. Personaly, I love the sound of the turbo hissssssssssss. sit back and enjoy it. Wait till you upgrade the exhaust system and you will sound like a fighter jet rolling down the highway.

If it really bugs you though. Have a good diesel mech look at it for you for piece of mind.

Scott

[over200]

Originally Posted by Cyclist 06

don't worry about it, it's normal. My 06 does it and it gets louder with each mod. Personaly, I love the sound of the turbo hissssssssssss. sit back and enjoy it. Wait till you upgrade the exhaust system and you will sound like a fighter jet rolling down the highway.

If it really bugs you though. Have a good diesel mech look at it for you for piece of mind.

Scott

Oh I know what your saying and I love the sound too but the sound Im talking about is not normal!!! Think of the hissing sound your hearing and then add a major skip in it while it is hissing instead of the sssssssssssss it's sssstststststststssssssssssssstststststststsssssss ssststststststttttttttt.

[99Smokin73Stroker]

It's normal, mine did it too from the day I bought it until the day I sold it.....I heard it more in 3rd during higher rpm's and boost levels......