98 Jetta AHU Stalls and then re-starts

verdigo

New member
Joined
Sep 19, 2015
Location
Cave City Kentucky
TDI
98 Jetta
So like the title says it stalls. This happens when under a moderate load but definitely when I stick my foot in it a little bit. I could even say under normal driving. As soon as it stalls all I have to do is cycle the key even without going to the start position and operating the starter. While it is coasting down still in gear with the engine turning, I just cycle the ignition switch to off and back to run and it picks up. I am guessing maybe the shutoff valve/switch on the pump. It only has a half million miles on it though. What do you guys think?

Thanks

Dennis
 

Steve Addy

Top Post Dawg
Joined
Aug 7, 2002
Location
Iowa
TDI
97 Mk3
So like the title says it stalls. This happens when under a moderate load but definitely when I stick my foot in it a little bit. I could even say under normal driving. As soon as it stalls all I have to do is cycle the key even without going to the start position and operating the starter. While it is coasting down still in gear with the engine turning, I just cycle the ignition switch to off and back to run and it picks up. I am guessing maybe the shutoff valve/switch on the pump. It only has a half million miles on it though. What do you guys think?
Thanks
Dennis
Any CEL from this activity?

Steve
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Something is triggering limp mode and cycling power clears it, until the ecu sees the fault again. If it’s not triggering a CEL, scanning the car will usually find it.

-Todd
 

Abacus

That helpful B4 guy
Joined
Nov 10, 2007
Location
Relocated from Maine to Dewey, AZ
TDI
Only the B4V left
Is it stalling or just going into limp mode that needs to be reset by a key cycle?

If it's shutting down, it's probably electronic, so check the black/white wire by the fuel pump. it's known for chafing through and I've found this to be the problem a few times.



 
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