TheSamba.com :: View topic - 2003 Eurovan - occasional stalling, lumpy idle, P1165, no CEL

Tue Jun 24, 2025 1:01 pm

Hello folks,

I'm trying to diagnose an issue with my '03 Eurovan MV (VR6 with 200K miles) and am looking for advice because I'm about to take an 1,800-mile road trip with the kids later this week.

Here are the symptoms:
- No CEL
- VCDS reports P1165 (system too rich, intermittent)
- The idle is occasionally lumpy and stalls when the engine is hot.

I've owned the car for about three years and it's never stalled on me (ever!), so this is strange behavior.

I'm wondering if I need a new secondary air injection pump, new (cleaned?) MAF, or something else. Any tips on where to locate and replace the air injection pump would be helpful, but I can't imagine it's that because the issues I'm encountering are _after_ it's warmed up.

Any input?

Thanks,
Dan

Tue Jun 24, 2025 1:31 pm

Have you used any fuel injector cleaner, Techroline, in the fuel tank?
You may have an injector that is not flowing correctly.

Someone smarter that I, will be along to lend a hand with your issue.

Tue Jun 24, 2025 1:50 pm

Thank you @rust, I used BG 44K a while back and I only put 91+ in it, but I'll try an injector cleaner before I take it to the shop on Friday.

Tue Jun 24, 2025 2:54 pm

Try clamping off the hose from your N80 valve to the throttle body. The N80 valves sometimes fail open which allows an air leak from the charcoal canister into the intake. Depending on how saturated your charcoal canister is, that could result in rich or lean codes.

Doing this will throw an evap code and CEL, but that can be easily cleared after you've ascertained whether your symptoms have improved.

Tue Jun 24, 2025 4:45 pm

Sweet... thank you @trunnion. I'll give that a shot tonight!

Tue Jun 24, 2025 6:20 pm

So, I tried clamping off the N80 valve as @trunnion suggested. It didn't seem to have any affect on the engine (which was running very smoothly), but I did get an additional EVAP code (P0441, incorrect flow -- no CEL, still, though).

I cleared all of the DTCs and ran readiness -- it returned about six "failed or not ready".

Next I went through the readiness reset (except for all of the driving parts) and most of the codes cleared. Here's the Address 01: Engine scan from my VCDS:

Code: Tuesday,24,June,2025,20:56:16:20611
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 11 x64
VCDS Version: 25.3.1.1 (x64) HEX-V2 CB: 0.4671.4
Data version: 20250415 DS365.0
www.Ross-Tech.com

VIN: WV2MB47093H035863 License Plate:

Chassis Type: 70 (7D - VW Transporter/Multivan (1996 > 2004))
Scan: 01 02 03 08 15 17 18 19 22 25 35 37 56

VIN: WV2MB47093H035863
-------------------------------------------------------------------------------
Address 01: Engine Labels: 022-906-032-AXK.lbl
Part No: 022 906 032 AF
Component: MOTRONIC ME7.1 G 0003
Coding: 00013
Shop #: WSC 02760
VCID: 4FFB61129EC82442460-51A8
VINID: 9E609D4841C02436000C52060C7FBF5F71

1 Fault Found:
17978 - Engine Start Blocked by Immobilizer
P1570 - 35-10 - - Intermittent
Readiness: 0000 0100

I had one "false start", which felt like the immobilizer kicking in, when I restarted the engine -- that explains the intermittent P1570 above.

This means that "EVAPORATIVE EMISSIONS" (the sixth "one" above) is the only failed readiness item that I have... which is great news -- I can get the car inspected in NYC, where we can have only one failure.

But it's strange that I don't see the EVAP fault code associated with the one failed readiness item in the VCDS scan. Anyone know why?

Is it because I was unable to complete the EVAP readiness item successfully? (I remember I had to "next" through a few items). Will the EVAP (large leak) return as a DTC after I drive it a few hundred miles?

Tue Jun 24, 2025 6:28 pm

dbeeby wrote:
But it's strange that I don't see the EVAP fault code associated with the one failed readiness item in the VCDS scan. Anyone know why?

Evap codes don't set until the fault persists over several drive cycles. Drive it a few more times and it will pop up.

Tue Jun 24, 2025 6:41 pm

trunnion wrote: dbeeby wrote:
But it's strange that I don't see the EVAP fault code associated with the one failed readiness item in the VCDS scan. Anyone know why?

Evap codes don't set until the fault persists over several drive cycles. Drive it a few more times and it will pop up.

Alright. I'm taking it to the shop on Friday and I'll see if they can find a leak or other issue.

Tue Jun 24, 2025 6:50 pm

If the engine was running smoother after you clamped off the N80 valve, then the valve is probably bad. Take it off the car and blow through it. Valve should not let air pass when de-energized.

Tue Jun 24, 2025 6:59 pm

when it stalls, does it restart right away, or does it take 10-15 minutes?

Tue Jun 24, 2025 7:37 pm

67rustavenger wrote: Have you used any fuel injector cleaner, Techroline, in the fuel tank?
You may have an injector that is not flowing correctly.

Someone smarter that I, will be along to lend a hand with your issue.

Yes too rich, too much fuel, a dirty, leaking injector(s)- will cause hard starts, rich conditions esp when hot. Cold start the fuel mixture in enriched anyway so it's not so noticeable.

Wed Jun 25, 2025 7:28 am

Hello folks, thanks for the feedback.

@trunnion, I didn't notice a difference when the valve was clamped shut or open to breathe. I will remove the valve and ensure that it's "closed".

@dodger_tom: yes, when it stalls it cranks and restarts right away. I don't think it's vapor lock, though it has been exceptionally hot on the East Coast this week, which might explain some of the symptoms.

@SambaBurnsRed, I'll get some injector cleaner, but at 200K miles I might be due for that service (I don't know if it's ever been done).

I'll report back if I learn anything new.

Wed Jun 25, 2025 9:29 am

dbeeby wrote: @dodger_tom: yes, when it stalls it cranks and restarts right away. I don't think it's vapor lock, though it has been exceptionally hot on the East Coast this week, which might explain some of the symptoms.
my brother’s ‘99 had the symptoms of vapor lock. it’d stall, then restart after 10-15 minutes. hot weather made it worse.

it was the fuel pump.

there’s a thread about it around here somewhere.

good luck.