Limp Mode - Very Odd

TDIPASSATGUY

Veteran Member
Joined
Dec 7, 2005
Location
ROSWELL, GA
TDI
2005 GLS Passat Sedan
Engine braking/Coasting at 80 MPH down a steep mountain grade I-75 at the TN-KY border. Limp mode "EMISSION WORKSHOP" and Yellow engine light on. Shifted to N. STOP START back to normal but with engine light and "EMISSION WORKSHOP" light on. It did this one more time 30-40 miles later under the same conditions.

Connected to VAG COM this morning and ran the scan.
01,01,03,16,17,46,56 = NO FAULTS FOUND or DTCs not supported by controller or A communication error occurred

SKIP 15
19 = EXCESSIVE COMM ERRORS

I don't use VAC COM much and can't quite remember what the results look like from a clean scan.

After a couple of starts, the "EMMISION WORKSHOP" and yellow engine lights have gone away.

WAY BACK - I had this problem right after chipping, but it was after HARD accelleration, perhaps occurring when I let off that may duplicate the engine braking I was doing yesterday. IT CODED 'lower than expected boost pressure" then and we assumed a leak in the turbo hose system. 50K miles later, this.
 

dieseldorf

Top Post Dawg
Joined
Oct 11, 2000
Location
MA
TDI
ex- 1996 wagon, ex-2000 Jetta
Strange. Are you going to have the dealer look at it? Do you have someone you can trust? I can't say I've seen errors like that before but don't have any direct experience since we don't see those cars (very often) in CARB states :(

The emissions warranty doesn't run out when the base warranty runs out ;)
 

TDIPASSATGUY

Veteran Member
Joined
Dec 7, 2005
Location
ROSWELL, GA
TDI
2005 GLS Passat Sedan
I'm not sure if I'll get a dealer on it or not. It reset as soon as I shut down and re-started, and VAG COM didn't show a code. No power or economy loss. It was the same lights you would get if the fuel cap were loose. WIth out a code, the VW guys would be in the dark. I'll check the air filter. It is amazing how much junk can make it into that little air snout. The cumulative amount of debris I have cleaned out of every other car I have ever owned is no where near the 6 month build up I get on the car. It is like an interstate vacume cleaner. I'm wondering if there is a possiblity of a boost hose leak. Is there a portion of the circuit under vacuum under those conditions? If so I could get a vaccum leak in the same joint that seals pressure fine....
 
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TDIPASSATGUY

Veteran Member
Joined
Dec 7, 2005
Location
ROSWELL, GA
TDI
2005 GLS Passat Sedan
The snow screen had a handful of leaves cigarette butts and gravel. I will get a new filter as well. Hopefully that was the problem.
 

TDIPASSATGUY

Veteran Member
Joined
Dec 7, 2005
Location
ROSWELL, GA
TDI
2005 GLS Passat Sedan
Air filter dirty and the box hand another hand full of gravel, butts, and leaves. Another trip next week....crossing fingers.

Do I have an N75 valve? Are they problems on this model like they seem to be on the 1.9s?
 

TDIPASSATGUY

Veteran Member
Joined
Dec 7, 2005
Location
ROSWELL, GA
TDI
2005 GLS Passat Sedan
I also changed the N75 and NO MORE PROBLEMS. So either the grimlen went elsewhere, or the parts changes have fixed it.
 

gbangs

Veteran Member
Joined
Jul 1, 2003
Location
United States
TDI
None currently
I had the same thing just this week..
The Emissions Workshop Light comes from not enough EGR flow... due to not enough boost to push the gases through(IMHO)

Though, I had a Boost Control Pressaure Not Achieved code. P0299. I pulled my n75 valve and sprayed brake cleaner through it and it now works great... I do know it is only a temporary fix.
 

Smokerr

Veteran Member
Joined
Sep 3, 2005
Location
Alaska
TDI
Passat Wagon GL,2005,Silver
We went through that. Upshot was they replaced the N75, but did not cure.

The Turbo mechanism was sticking occaisonaly, they replaced the turbo. No repeat, and much better off the line, so some stick all along I think.
 
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