# Location of turbocharger "Overrun Cutoff Valve"???



## Fab64 (Jan 21, 2005)

Hi all,
I have a 2001 Beetle GLS, with 1.8t (AWV) engine and 5 spd tranny. Unlike many people I've read about on various boards, my car has been relatively trouble-free for 40k miles, has never left me stranded, and is a total blast to drive. My only real complaint is with the various warning lights that flash/beep occasionally, often for no apparent reason. 
Recently, my local dealer (Fladeboe VW in Irvine, CA) told me the cause of my current Check Engine light is a bad turbocharger "Overrun Cutoff Valve"







, for which they want $106 to replace. 
I have the Bentley service manual but I am unable to locate this specific part. The closest things I can find are on page 21-13, where an "*Overrun Recirculation Valve*" and an "*Overrun Recirculation Valve Solenoid*" are shown (items 12 & 18). Are either of these the correct part? If not, does anyone know what/where the "Overrun Cutoff Valve" is? And is it something I can replace myself without too much difficulty? I'd appreciate any tips. Thanks very much.
Roger


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## DerGolfGTI (Feb 21, 1999)

*Re: Location of turbocharger "Overrun Cutoff Valve"??? (Fab64)*

Its possible that what the dealer might have meant is the N75 valve. This valve controls the turbocharger's wastegate, and if the valve malfunctions, it can allow the turbocharger to build more boost than it should. The car's computer would recognize this condition and an "overboost" code would be stored in the car's computer. 
The computer may also decide to put the car into what is sometimes referred to as "limp" mode - deliberately limiting the power the engine produces to prevent any damage. In this mode, the car drives almost like you'd expect if the turbo wasn't there. It works, but not so much fun.
The N75 valve runs about $75 and is easy to install, so your $106 price is not out of the ballpark if this is the part the dealer really meant.
Of course this is just one possibility.
Regards,
Tom
98 GTI (VR6)
00 Bug (1.8T)


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## 1.8T_Moe (Sep 19, 2004)

*Re: Location of turbocharger "Overrun Cutoff Valve"??? (DerGolfGTI)*

Yeah I would agree about the N75 valve but if it was bad I think you'd overboost all the time which would put you in limp mode all the time, which you would definitely notice. Have you noticed any changes in power while driving?
Calling it a Cutoff Valve would make it seem like the N75 though. And price wise that sounds about right as DerGolfGTI said.
Post in the 1.8T forums and you can find out for sure probably.


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## Fab64 (Jan 21, 2005)

*Re: Location of turbocharger "Overrun Cutoff Valve"??? (1.8T_Moe)*

No, I haven't noticed anything out of the ordinary (except for the light). I guess I need to call the dealer back and get clarification.
And I didn't realize there was a separate 1.8T forum - I'll try posting there.
Thanks for the suggestions.
Roger


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## water&air (Aug 1, 2002)

*Re: Location of turbocharger "Overrun Cutoff Valve"??? (1.8T_Moe)*


_Quote, originally posted by *1.8T_Moe* »_Yeah I would agree about the N75 valve but if it was bad I think you'd overboost all the time which would put you in limp mode all the time, which you would definitely notice. Have you noticed any changes in power while driving?
Calling it a Cutoff Valve would make it seem like the N75 though. And price wise that sounds about right as DerGolfGTI said.
Post in the 1.8T forums and you can find out for sure probably. 

vw reffers to both the n75 and d/v as a "cutoof valve", stupid i know.


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## 1.8T_Moe (Sep 19, 2004)

*Re: Location of turbocharger "Overrun Cutoff Valve"??? (water&air)*


_Quote, originally posted by *water&air* »_
vw reffers to both the n75 and d/v as a "cutoof valve", stupid i know.









Guess they should number then then. "Sir your cutoff valve #2 is bad."


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