TheresaM
Member
Glow plug light flashed with check engine light at initial sequence for start. Coded two faults P0651 (sensor reference voltage B circuit) and P0322 (engine speed imp. circuit no signal). Mileage on vehicle 180,251. Car towed and VW dealer replaced engine speed sensor. Car ran fine till about the third time I was ready to run an errand and the glow plug light flashed with check engine light. Car towed to VW dealer. What we are able to deduce is it's intermittently coding P0322 (engine speed imp. circuit no signal) fault only when vehicle is parked on roughly 15degree incline (same incline as my driveway). Even then the mechanic noted the fault ultimately went away in a few minutes. Mechanic did multiple 10 minute trips and could not reproduce the fault. Given it's positional, the mechanic thinks this may be moisture triggering a short. But they would need to pull apart the harness to find it and even then can't guarantee they will find the shorted wire(s) or if other internal components may be damaged as a result of the initial short. If they can't find it and need to replace the entire harness could run me more than the car's value.
Has anyone run into a positional, intermittent P0651 fault previously or has had the fault triggered by moisture? If so, what caused the water intrusion? Windshield gasket failure, or other? I would think if it's a positional, intermittent fault triggered by moisture on a vehicle with very limited movement since faults started (max travel time 20-30 minutes) then we should only be talking about a few corroded wire leads at worse case versus the need to replace an entire harness. Does this make sense or is there something more intrinsic to this Jetta TDI build that would complicate this repair?
Edit: Water intrusion not evident nor completely ruled out. No corrosion of connections or grounds observed. Fault only able to replicate when vehicle parked for a period of time on an incline.
Has anyone run into a positional, intermittent P0651 fault previously or has had the fault triggered by moisture? If so, what caused the water intrusion? Windshield gasket failure, or other? I would think if it's a positional, intermittent fault triggered by moisture on a vehicle with very limited movement since faults started (max travel time 20-30 minutes) then we should only be talking about a few corroded wire leads at worse case versus the need to replace an entire harness. Does this make sense or is there something more intrinsic to this Jetta TDI build that would complicate this repair?
Edit: Water intrusion not evident nor completely ruled out. No corrosion of connections or grounds observed. Fault only able to replicate when vehicle parked for a period of time on an incline.
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