[TommyFan101]

Hello, I have a 2000 VW Beetle with the 1.9 TDI engine. A few months ago I was driving my car and the engine shut off on the highway. The weather was bad and it was cold so I thought it might have something to do with that. I tried to start it back up but it wouldn't start. I looked online and found a suggestion to unplug the MAF sensor. I did that and I was able to get the car home. The next day I plugged the sensor in and the car ran fine. Recently I was having similar issues so I replaced the MAF sensor but that didn't fix the problem.

Currently the car doesn't always start when I try to crank it. If it does start it will usually shut of if I give it some throttle, if I let it warm up it will often run better. I have a Ross-Tech cable and was checking some values with VCDS. It appears that the expected and actual boost values for the turbo are not the same. When I give it throttle the expected boost value goes up but the actual boost value doesn't change at all. On VCDS I checked for fault codes and did an auto-scan but nothing that came up looks like it is related to the problem.

What should I do to troubleshoot the problem?

 

[Moonshot Rattle Bucket]

You might want to start by checking the intake for a buildup of soot blocking air flow.

 

[TommyFan101]

I took the large pipe off on the passenger side. I think it goes to the egr valve. It was a little dirty but not blocked. How to I check the intake? Here's a forum I've been posting on with more info. Currently I can't get the car to start at all.
1.9 TDI 2000 VW Beetle Engine shuts off

 

[Moonshot Rattle Bucket]

Some symptoms you describe could point to a anti-shutter valve vacuum leak. The ASV is held open by vacuum while the engine is running, so if there is not enough vacuum against the spring tension that is trying to close it, it can close and kill the engine, or it could only partially open. Someone else on the other thread suggested a Mityvac (handheld vacuum pump). Definitely a good idea. checking vacuum lines and leaks is really the first thing to do. Once you've determined they're holding vacuum, and if still have the problem then could be turbo actuator, N75 or vacuum pump. All of those you can also check with a Mityvac. So highly recommend getting one if you don't already have one. Is your 'requested' boost the green or yellow line in the graphs?

 

[TommyFan101]

The requested boost is the green line so the yellow(actual) is not getting quite high enough. I got a Mityvac so I can start testing those vacuum lines.

 

[Moonshot Rattle Bucket]

You may have more than one issue going on. . with the stalling. check this similar stall no start problem and what resolved it.

Stalling issues with 2005 Jetta GLS TDI

For the past year I have been daily driving a 2005 Jetta GLS TDI with 5-speed automatic transmission. It has 276k miles on it and otherwise runs fine. The issue I’ve been having these past few months is at idle speeds the car will stall, this means at stop lights or creeping behind traffic the...

www.myturbodiesel.com

 

[joediesel]

Have you checked your relay 109? I haven't dealt with that in a few years since changing to the new relay (I believe the old ones were gray, new ones are black) so rather than giving you have memories of location and testing procedure I'd recommend you search for relay 109 to get full procedures and location. That being said, the lights on dash when not starting give a good indication of a failed relay 109. I had your exact symptoms back in the early 2000's with 109, on the highway car just died, fortunately restarted. Subsequently driving a 13 hour trip it dies again, fortunately started and drove it to a dealership who charged me 300 dollars to find the problem. After that I read everything about Relay 109. Now I keep a spare relay in the glove box but haven't needed it since changing to the new style. BTW, Relay 109 is under the dash above the drivers left foot, you need to be a good contortionist to get to it.

 

[TommyFan101]

I know I'm having some issues with the vacuum system so I'm starting with that. I've had a few people suggest the 109 relay so I might go for that once I'm done with the vacuum system. Sounds like I should go ahead and get one and keep it around as a spare.

 

[UhOh]

"On VCDS I checked for fault codes and did an auto-scan but nothing that came up looks like it is related to the problem."

How confident are you that any such codes are NOT relevant? Almost all issues should register through some sort of code.

Stalling out sounds like fuel is being shut off. Possible bad wire/connection to the IP solenoid shutoff valve. If it's air blockage, which it could be, I'd think that you'd have a slow-down/loss of revs before the engine completely stopped: if the ASV closes that would cause an engine stop; why that's happening when running is something I haven't heard of (but I cannot say I've heard/read of everything); vacuum is applied to close the valve, so something would have to engage vacuum and keep it engaged- possible, but not real probable (though, again, not good to rule out; I'd put it on a list of things to check, put it at the bottom of a list).

I'll put out a pitch to always run with a ScanGuage or an UltraGuage. There's enough stuff to monitor via these that they can be very helpful to catch problems (not at a VCDS level, but they're a useful tool).

 

[Moonshot Rattle Bucket]

True. Lots of symptoms VCDS won't throw 'specific' component codes for. For example limp modes which have lots of relevant possible causes.
You are correct about the ASV. I was thinking of it in reverse and it couldn't function that way. thanks for the correction!

How confident are you that any such codes are NOT relevant? Almost all issues should register through some sort of code.......
vacuum is applied to close the valve, so something would have to engage vacuum and keep it engaged- possible

 

[TommyFan101]

Here is the VCDS scan that I got when the car was running. Just some air bag and mirror heater things. I checked the anti shudder valve. It is staying open but the car won't start. Here's another forum I've been posting on with more information.
1.9 TDI 2000 VW Beetle Engine shuts off

Wednesday,27,April,2022,19:06:29:42197
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 22.3.1.4 (x64)  HEX-V2 CB: 0.4615.4
Data version: 20220407 DS337.0
www.Ross-Tech.com


Mileage: 181470km-112760mi   Repair Order:



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Chassis Type: 1C - VW New Beetle (1998 > 2010)
Scan: 01 02 03 08 15 17 19 25 29 35 37 39 46 54 56 65 75
 
   Mileage: 181470km-112760miles
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 038-906-012-AGR.clb
   Part No: 038 906 012 N
   Component:  1,9l R4 EDC G000SG  2509 
   Coding: 00002
   Shop #: WSC 00066 
   VCID: 1B63D9D2FABF8D833AD-4B1E

No fault code found.
Readiness: 0 0 1 1 1

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 1J0-907-37x-ABS.clb
   Part No: 1J0 907 379 P
   Component: ABS     20 IE CAN  0001 
   Coding: 03504
   Shop #: WSC 00066 
   VCID: 3E253046496DF8ABFD3-4B3C

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 6Q0-909-605-VW5.lbl
   Part No: 6Q0 909 605 A
   Component: 06 AIRBAG VW5       0003 
   Coding: 12342
   Shop #: WSC 00066 
   VCID: 35372F6A7C5B3BF32C9-4B3C

4 Faults Found:
00655 - Seat Belt Tensioner Igniter; Passenger Side (N154)
            32-10 - Resistance Too High - Intermittent
00532 - Supply Voltage B+
            07-10 - Signal too Low - Intermittent
01218 - Side Airbag Igniter; Passenger Side (N200)
            32-10 - Resistance Too High - Intermittent
01317 - Control Module in Instrument Cluster (J285)
            49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 1C0-920-xx0.lbl
   Part No: 1C0 920 901 A
   Component: KOMBI+WEGFAHRS. M73 V02 
   Coding: 03202
   Shop #: WSC 00050 
   VCID: 1A6DDCD6F585F48B21B-4B1E

   Subsystem 1 - Part No: Ident
   Component: Nr. Wegfahrs.:VWZ5Z0X8252381 
   Ident.-Nr. Wegfahrs.:VWZ5Z0X8252381

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels: 6N0-909-901-19.clb
   Part No: 6N0 909 901
   Component: Gateway K<->CAN    V022 
   Coding: 00006
   Shop #: WSC 00066 
   VCID: 70B9DE7E43B95EDB3FF-4B1E

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels: 1J0-959-799.lbl
   Part No: 1J0 959 799 AJ
   Component: 5X Zentral-SG Komf. 0001 
   Coding: 00256
   Shop #: WSC 00066 
   VCID: 065598A6513D606BF53-4B1E

   Subsystem 1 - Part No: 1J2959802C
   Component: 5X Tõrsteuerger. FS0002r 

   Subsystem 2 - Part No: 1J2959801D
   Component: 5X Tõrsteuerger. BF0002r 

4 Faults Found:
00943 - Heated Exterior Mirror; Driver Side (Z4)
            35-00 - -
00913 - Window Regulator Switch; Front Right Driver (E81)
            27-10 - Implausible Signal - Intermittent
00933 - Electric Window Motor; Passenger Side (V148)
            62-10 - No or Incorrect Adjustment - Intermittent
00944 - Heated Exterior Mirror; Passenger Side (Z5)
            35-00 - -

End----------(Elapsed Time: 03:46, VBatt start/end: 14.2V/14.2V)-----------

 

[UhOh]

OK, thanks for the logs...

I'm still leaning toward fueling (if the ASV isn't sticking, not likely an airflow issue). Do you see fuel flowing in the fuel filter line (if it's clear)? I'd check that the voltage at the IP shutoff; and keep in mind that this wire could be flaky, resulting in intermittent issues: others can chime in as to whether it might be instructive to run a direct wire from the battery just to test (not sure what the actual voltage is for the valve, so word of caution here).

 

[TommyFan101]

I've bled the fuel system just to be sure. I checked the IP shutoff valve. It's getting voltage and clicks when the key is turned.

 

[UhOh]

Are you getting ample fuel pumping out of the injectors if you crack open lines?

"Intermittent" means that something can work one second and not the next. Electrical stuff can be like this. Do not assume that there's constant voltage at the shutoff valve.

MAF issues won't cause your engine to stop: at worst ECU will go into limp mode. Airflow blockage (you've already ruled out the ASV) is the only real mechanical thing that I can think of (other than some sort of catastrophic failure) that can cause an engine to just stop.

Electrical issues are more likely to cause abrupt shutdowns. IP shutoff valve (still cannot rule this out as it could be intermittent) or ignition. Not a bad idea to verify/clean grounds.

IF you can get the engine to run try logging injector balance. These numbers can tell a lot: if you've got a bad cylinder, which could be a problem here, it'll likely show up (it's a backdoor way to check for a bad cylinder or two). NOTE: when you say that depressing the accelerator helps this suggests that there could be a fueling imbalance.

Feels like there's a primary issue and a secondary one occurring: ignition issue and fueling issue?

 

[TommyFan101]

I found the problem! It's the crankshaft position sensor wire.

 

[UhOh]

Great! I was going to mention the CPS but thought that problems would get logged (apparently not?).

This is a reminder/example of the need to watch the wiring on these cars as they're aging.

 

[TommyFan101]

I did get a crankshaft position sensor code. I replaced the sensor and assumed that had fixed that problem. Apparently I didn't look closely enough at the wire when replacing it.

 

[UhOh]

Cabin fan in one of my tractors quit working after it was about 4 years-old. I was just about to give up troubleshooting when I decided to start yanking on wires (with the fan switched/powered on) and lo and behold the fan kicked on. It was a factory defect: some sort of wire-holding device or connector install had crimped the wires such that they got broken inside the insulation. Really hard to rule things out when it comes to electrical issues! But, nice to hear that you're now free of this headache.