[Sgtsly]

My Passat is running like shit and I'm at my wits end. Keep throwing 9 codes. I know they are all tied in together. 2001 Passat 1.8t AWM
260k miles

P0445 P0141
P0245. P0031
P0037. P0102
P0418
P0414
P2400

I know what the codes are. Boost(n75) , MAF , 02's , SAI , evap however I can't figure out what the fuck is going on. They all tie in somewhere. I have checked grounds, fuses relays and still come up short. Someone plz help

 

[jjpark]

More info on the car itself would be helpful. Yr, mileage, past history,

Have you checked for vacuum leaks?

 

[sirwired]

"vac leak" was my first thought too. If you have a car that was equipped with the cloth-braided vac hoses they all need to be replaced, because they suck. Even the better rubber hoses are not exactly fresh from the factory at this point.

 

[Sgtsly]

Yo all are serious about looking for a Vac leak?

 

[kutcht1]

Checking for leaks is and easy fix and you need to at this point start eliminating things you can without throwing parts at it. 260K miles is a lot of miles and it could easily be a rubber hose. Other than finding out what the codes are and looking at grounds, relays and fuses what else have you done?
TomK

 

[sirwired]

Why wouldn't we be serious? Vac leaks can cause a lot of fascinating drivability problems.

 

[FrescoGreen01.5]

I wasn't able to match up all you P-codes to the VW-specific codes, but I'd say to check fuse 34.
It powers pretty well everything you're getting a code for...

In the AWM 1.8T, fuse 34 powers:

• SAIP relay
• Evap valve N80
• Wastegate bypass regulator valve N75
• SAIP solenoid valve N112 (pilot valve for the combi)
• Recirc valve for turbo N249
• Pre-cat O2 sensor
• Post-cat O2 sensor
• MAF sensor
• Leak detection pump

The wire is green/yellow under the hood, but red/green to the leak detection pump.

Reference: Bentley schematic 49/4-6, & 49/11.

 

[VAGguy]

P0445 is purge valve short circuit

16629/P0245/000581 - Ross-Tech Wiki

Phttps://www.autocodes.com/p0037_volkswagen.html

https://www.autocodes.com/p0418_volkswagen.html

https://www.autocodes.com/p0414_volkswagen.html

P2400 is leak detection pump open circuit or failed pump. Check wiring and pump.

16525/P0141/000321 - Ross-Tech Wiki

http://wiki.ross-tech.com/wiki/index.php/16486/P0102/000258

https://www.autocodes.com/p0031_volkswagen.html


They do all tie into the ECU. Have you removed the ECU for any reason prior to this? Open up the ECU box and check the fuses/relays in there as well. How did you check the other relays for proper operation? " I have checked grounds, fuses relays" when we see this statement, it usually ends up that not all were checked/found or checked properly.

While Vac leaks are extremely common on the B5s as they age, the majority of these codes point to electrical connection issues. It is important to make sure no pins are bent when reconnecting plugs. It could be something as simple as that. Also, do not leave out anything you have done to the car recently, even if you may have already dismissed a possible connection in your head with the current issue.

 

[jjpark]

Yo all are serious about looking for a Vac leak?

As a heart attack. It's a pretty common thing to happen on these aging cars as others have pointed out.

 

[Tomvw]

1: Check fuse #34.
2: Check fuse #29.
3: Check ECM power supply relay. (in ECM box)
4: Check wiring in above circuits.
5: Check for vac leaks.

 

[FrescoGreen01.5]

BTW, the ECM will set "[device] open or short to ground" codes when there is no +12 volt power to the device (valve, relay coil, etc.).

The ECM switches the ground side of the circuit, not the positive side, like you might expect. The positive side of everything the ECM controls is connected directly to +12 volts. In the case of the items I listed in Post #7, that +12 volts comes from fuse 34 (for the AWM engine).

 

[Sgtsly]

ECU hasnt been touched since my reprogram 4 years ago. I work as a heavy mechanic and have nothing but VW's my whole life. I know common issues and so forth. I have opened the ecu box last week and checked fuses inside there. 12v on each side of posts. as far as all the other fuses and shit I went one by one with a test light, then meter and pulled one by one just for shits and giggles on every fuse in the fuse box and fuses located under/behind steering column.
I will start looking into some of these other ideas posted as well when its not 18 degrees outside. my shop is in a secure area so its hard to get my car in and out of the shop.

 

[Sgtsly]

The car starts right the fuck up every time no hesitation i find it hard at this point to not want to burn this bitch. i HAD water issues with the bcm 2 days before this started with a key on not start issue. but dried it out cleaned it up car started up just fine then the next day this.

 

[Sgtsly]

I dont mean to sound stupid but is there really any way a vac leak could cause all these issues? i could see a drivability issue maybe a stumble but not make it run like this right?

 

[Sgtsly]

IS there any fucking way in hell these can be caused from the BCM?

 

[Tomvw]

The car starts right up every time no hesitation i find it hard at this point to not want to burn this bitch. i HAD water issues with the bcm 2 days before this started with a key on not start issue. but dried it out cleaned it up car started up just fine then the next day this.

There could be water damaged wiring in the dash.

I dont mean to sound stupid but is there really any way a vac leak could cause all these issues? i could see a drivability issue maybe a stumble but not make it run like this right?

Not likely, but the ECM power supply relay is very likely.

IS there any way in hell these can be caused from the BCM?

No the CCM could not cause these issues, but water damage is a possibility.

 

[Sgtsly]

At this point I'm running out of ideas and patience. I'm going to the junk yard and grabbing a PCM and see what happens l.

 

[Tomvw]

I assume you mean the CCM in the Passat, some car makers call it a BCM or BCU.
Make sure to get the exact same part number, B5 CCMs are totally non-compatible with B5.5s. Note: The remotes will need to be re-matched.

Of course this won't have any effect on the bad running, or most of your codes.

 

[FrescoGreen01.5]

Referring to post #7: do you have +12 volts on the green/yellow wire with the key on (no need to start it)? The N75 & N112 valves (underside of intake), or the N80 valve (over right front wheel) would be easy places to test.

If, as I suspect, you don't have +12 volts there, then that's your problem. It would cause most/all of the codes you've got.

 

[kutcht1]

Do we really need to swear in almost every post to get our big boy point across? We understand issues can be frustrating but reading through a gang novel does not make people want to dig into the issue and lend a hand, just saying.
TomK