TheSamba.com :: View topic - 87 Syncro

Mon Jul 28, 2025 10:15 am

and one more issue to deal with...:)

My van has a GenV Jetta Engine 2.0L recently "went limp", underpowered, out of nowhere seemingly.
I found I had two codes:
P2138: throttle/pedal position sensor
P0172: running rich

Fixed the pedal position sensor and it has not gone limp again. Seems to be running fine.
But the running rich code persists.
Changed the spark plugs, wires look ok. Muffler/oxygen sensor were pretty recently replaced. I don't have any dash lights currently.

What else do you suggest I check?

1987 Syncro Camper Van/Country Homes Camper Poptop

Mon Jul 28, 2025 10:25 am

What motor are you running?

Mon Jul 28, 2025 11:46 am

From his other thread:

Quote: GenV 2.1L Jetta Engine
Yeah, good to know specifics.

:wink:

- Dave

Mon Jul 28, 2025 1:17 pm

I edited original post to include the Engine - 2.0L GenV Jetta.

Mon Jul 28, 2025 1:26 pm

Do you mean a Foreign Auto Supply Gen 5 2.0 Liter conversion?
That's an engine swap, and will have very specific issues that would likely best be answered by Foreign Auto Supply (The company making and supporting that engine, out of Maine).

Mon Jul 28, 2025 4:13 pm

Phishman068 wrote: Do you mean a Foreign Auto Supply Gen 5 2.0 Liter conversion?
That's an engine swap, and will have very specific issues that would likely best be answered by Foreign Auto Supply (The company making and supporting that engine, out of Maine).

Yes you're correct, 2.0 (original engine was 2.1). It is an engine swap. I had reached out to my mechanic here in Seattle who did the conversion, but hadn't heard back yet today...hadn't thought to reach out to FAS, thanks. Good idea.

Tue Jul 29, 2025 5:58 pm

The fault codes you have listed are generic OBD II faults. Your engine is a VAG unit. The ECU actually thinks in VAG specific codes. The OBD II faults are mandated as an overlay by federal law on this side of the pond.

The VAG specific fault code tend to be more specific than the generic fault codes. It would be useful to have access to the VAG fault codes and definitions.

But I would be looking at the throttle control system. Is it a full drive by wire system or an earlier hybrid system? Probably the former. Where is the throttle pedal sensor?