Lost all boost???

[Dayonaise]

hopefully i get a quick reply on what the **** is happening with my car now, anyways it was driving fine fore a few days and yesterday i took it for a drive to calgary, while on the highway it was responding just fine and if i needed boost it was there (only .5 bar 6-7psi) but then out of nowhere with no noise or engine sputter my boost quit, It still reads the vac fine on my gauge but will not let me boost at all as soon as it reaches zero on my gauge thats it. i have looked through all my piping and lines and there is no visible leaks or breaks, I removed the MAF and filter to see if the turbine was seized but the impeller is spinning freely with 0 shaft play so iam completely stuck as to why the turbo will not spool, its not burning oil and the engine is running fine as far as i can tell.
any and all help is greatly appreciated as iam sitting in my driveway as we speak trying to wrap my head around this

[cschepp]

Check to make sure your bov is tight and all your intercooler piping is good. Intercooler pipes are infamous for popping off and I have run into that problem a couple times. Give it a try man.

[cschepp]

I think you probably be fine checking for pipes as I bet it's that but if that doesn't work get some quick start and spray it in the area that you expect the car to be leaking air from. If there is a problem you should hear a change in idle

[Dayonaise]

will test that right now thanks, also there is no egr valve on these rb20's right?

[Skym]

Can have 0 boost when ceramic exhaust wheel wants to break shaft (turbo is out of balance) and take a walk down your exhaust. But usually happens when turbo overboost's, so I agree with intake airleak.

[Dayonaise]

i will pull the exhaust off right now and check that too, but my compressor impeller has no play and seems intact.
re-tightened all my intercooler piping and was surprised at how loose it actually was

[cschepp]

Let us know what happens. Want to know what cause the problem... If you don't mind telling of course

[Dayonaise]

Can have 0 boost when ceramic exhaust wheel wants to break shaft (turbo is out of balance) and take a walk down your exhaust. But usually happens when turbo overboost's, so I agree with intake airleak.

WOW MAN!!!!!! you are gods gift to skyline owners haha i would have never thought my exhaust wheel would desinigrate!!!! shes gone hahaha

[Dayonaise]

i will take pics as soon as i pull it.............****ing blew my mind!!!
Ps i have a rb25 45v4 does that have the same ceramic wheel or is that steel? i also have a 45v3 and a rb20 16v

[Dayonaise]

pics wont upload but you get the idea, clean brake bits of impeller scratched walls that kinda stuff.
Thank you so much skym

[amnash]

owned... lol

you suuuuure you were only running ".5 bar 6-7psi" ??

[cschepp]

Wow I wasn't expecting that! Shitty news. Oh well get it rebuilt or better yet do a hybrid turbo and then have some fun

[Dayonaise]

Already installed the rb25 45v4 and went burning around , it's all good

[Dayonaise]

owned... lol

you suuuuure you were only running ".5 bar 6-7psi" ??

as per my boost gauge ya, but it was on the highway and i was hitting in 5th passing a car so i was holding boost for a few seconds maybe it was too much?? either ay its sold tomorrow i picked up a 300zx TT fairlady today so that should be fun

[Skym]

WOW MAN!!!!!! you are gods gift to skyline owners haha i would have never thought my exhaust wheel would desinigrate!!!! shes gone hahaha

My guess is that turbo has probably done high km and was off balance, exhaust wheel hit housing, snapped shaft, etc (supposedly can do it at any boost level, depending on how out of balance turbo was). Also exhaust wheel usually ends up in middle of exhaust or can't be found. If next owner asks "what's that rattling sound from my exhaust", you'll know what it is.

pics wont upload but you get the idea, clean brake bits of impeller scratched walls that kinda stuff.

A mate showed me a photo on digital camera that he took of no exhaust wheel on RB20 stock turbo that overboosted. Was quite interesting.

Thank you so much skym

From everyone in this thread that helped, you're welcome.