Author Topic: my K24 sounds like it has a BOV (Read 6871 times)

James8485 · « **on:** June 13, 2008, 10:13:23 pm »

its really weird my bro has a 1.6L TD with the K24 and i just put one on my 1.9.....the thing is when he shifts from being in high boost you here nothing.....why i shift about 15 PSI it makes like a blow off valve sound.
so if im driving and am going through the gear shifting at 3500-4000 RPM
everytime i shift i hear a ksssssssss sounds like a blow off vavle but not that high pitch sound that a gasser makes..... this normal....maybe a leak somewhere??

vanagonturbo · « **Reply #1 on:** June 13, 2008, 10:48:55 pm »

turbo surge?

James8485 · « **Reply #2 on:** June 13, 2008, 11:26:21 pm »

whats turbo surge?

is this bad?

vanagonturbo · « **Reply #3 on:** June 14, 2008, 10:35:36 am »

its when the turbo spins backwards from decelerating too quickly and not having anywhere to vent pressurised intake. It can be very bad. One guy on here (old school Rich) had the shaft on his turbo break because of it and it. it can also cause the engine to run away.

spencebm · « **Reply #4 on:** June 14, 2008, 11:01:47 am »

normal

zukgod1 · « **Reply #5 on:** June 14, 2008, 09:59:58 pm »

Mine was that way, BAD BAD BAD!!!

Ended up snapping the shaft, bad deal.

I would drive nicer if I was you.

James8485 · « **Reply #6 on:** June 14, 2008, 10:14:04 pm »

well what do i do???
how do i fix this problem?? you guys say its bad for it to do that....why is it doing this? can i fix the problem? is it just my turbo is worn

vanagonturbo · « **Reply #7 on:** June 14, 2008, 10:48:31 pm »

you need to develop a system that can vent the pressurized (sp?) air to atmosphere or back into the intake stream. The factory had that plastic unit (you probably capped that off). Modify that and make it do the same thing, just with higher pressures.

If it makes you feel any better, my Scirocco does the same thing. I havent found a solution, nor have I tried as I am building a different engine with a different turbo right now.

James8485 · « **Reply #8 on:** June 14, 2008, 10:53:19 pm »

well ive been reading that if you have anyleaks from your comp to your intake it will make that sound after letting off the throttle
mine will have leaks as im waiting for my 2" elbow to come in so i riged up somthing with a 90 deg of PVC pipe and rubber ends but im sure it leaks as its pretty mickey mouse thnk that might have be causing it also!

the sound on my turbo spining baackward then back to forward sound painful!!!

ill just drive her slow till i get that turbo elbow to seal up the leaks

vanagonturbo · « **Reply #9 on:** June 14, 2008, 10:59:33 pm »

cruise control on=

DO NOT USE PVC FOR INTAKE PIPING!!

cruise control off.

James8485 · « **Reply #10 on:** June 14, 2008, 11:06:38 pm »

i know but i needed to get my car at least operational so i could drive it for the week so i was desperate........

i get that turbo elbow some time next week so thats good!

this turbo surging has got me alittle worried now though!

zukgod1 · « **Reply #11 on:** June 16, 2008, 10:07:56 am »

Its something your either going to have to just deal with or find a way to make a BOV that will work for diesels.
OR you can just keep spare turbo's to throw on WHEN you snap a shaft.

Maybe upgrade to a T4 with what ever AR and wheels you can get to work. That will be spendy when you can just drive nicer and keep the k24.

I'm looking for a better option as well, I don't like the turbo shaft being the weak link on my car. If that shaft had snapped when my wife was driving I would be replacing the engine right now.

jimfoo · « **Reply #12 on:** June 16, 2008, 10:16:17 am »

Quote from: "vanagonturbo"

you need to develop a system that can vent the pressurized (sp?) air to atmosphere or back into the intake stream. The factory had that plastic unit (you probably capped that off). Modify that and make it do the same thing, just with higher pressures.

If it makes you feel any better, my Scirocco does the same thing. I havent found a solution, nor have I tried as I am building a different engine with a different turbo right now.

Something I had thought about was using motorcycle reed valves in a box right after the turbo. Never did it though as I don't have surge problems.

zukgod1 · « **Reply #13 on:** June 16, 2008, 02:14:09 pm »

Quote from: "jimfoo"

Quote from: "vanagonturbo"
you need to develop a system that can vent the pressurized (sp?) air to atmosphere or back into the intake stream. The factory had that plastic unit (you probably capped that off). Modify that and make it do the same thing, just with higher pressures.

If it makes you feel any better, my Scirocco does the same thing. I havent found a solution, nor have I tried as I am building a different engine with a different turbo right now.

Something I had thought about was using motorcycle reed valves in a box right after the turbo. Never did it though as I don't have surge problems.

Something like that would probably work as long as you had a good fast working BOV so the pressure from the turbo had somewhere to go. I don't think isolating the turbo from upstream pressure build up will solve the problem unless you have a way to vent the pressure between the turbo and valve, am I making any sense at all???

bugnut · « **Reply #14 on:** June 16, 2008, 02:14:23 pm »

I would venture to say that it is turbo bark. Not a surge. If you let off the fuel slowly then it will not bark. Also try not to shift when on full boost. I had this happen on my dodge and matter of fact any diesel will do it when cutting fuel from full boost. Turbo still wants to spin but the air has no where to go but backwards which previous post alread said.