P0671 glow plug check engine light

davran

Well-known member
Joined
Feb 24, 2003
Location
Vancouver Island BC Canada
TDI
'05 Passat TDI Wagon
I had the check engine light come on, and checked it with my scantool.net obdlink MX tool and Torque pro on my phone. It showed P0671 code, #1 cylinder glow plug.

Funnily, I wiggled the wire where it connects to the plug, and so far it's stayed off.

But, when the glow plug code was thrown, the dash also showed: "Emissions Workshop", which went away when I cleared the P0671 code.
Does a glow plug code trigger the Emissions Workshop warning?

Thanks, Dave.
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
If the Vag says #1, its actually #4, get an ohmmeter, read the resistance of each glow plug, #4 will most likely be different than the other 3
 

Vince Waldon

Top Post Dawg
Joined
Apr 25, 2009
Location
Edmonton AB Canada
TDI
2001 ALH Jetta, 2003 ALH Wagon, 2005 BEW Wagon
A glow plug issue increases the emissions the engine makes, so will trigger a "Emissions issue, time to get me to the Workshop" message.

And yup, in case you weren't aware, the glow plugs are numbered in the opposite order to the cylinders ... for reasons known only to the German engineers what built 'er. :) : )
 
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afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
That is not my experience. If some hack has removed and replaced the harness, the glow plug wires/numbers may have been interchanged. Leads 1-4 and 2-3 are the same length and can be interchanged. From the factory they read 1-4 front to back.

A glow plug fault will trigger an "emissions workshop" message and will turn on the check engine light. A faulty glow plug can be intermittent, only failing occasionally when heated, or it could be a poor connection, Be sure to remove the plug and check the part number before ordering a new glow plug, there have been 3 revisions.
your wrong, there is no way you can interchange 1&4 and its tough to interchange 2&3
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
It happens. When the harness is removed, people always assume the longest lead goes on the front, that's wrong. The second longest goes there and the longest on the rear. They interchange easily. The two center ones are less likely to be interchanged.

are you sure your driving an 05 passat tdi wagen? You would have to remove the harness and cut the outer insulation to expose each individual cable, for what reason would anyone do this? My wagen harness travels out of the boughs of the engine, along the bottom of the head and each glo plug wire spirals from the harness to its respective glo plug. There is no way 1&4 would interchange. You can try to justify your argument but your wrong.
 
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oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
I had the check engine light come on, and checked it with my scantool.net obdlink MX tool and Torque pro on my phone. It showed P0671 code, #1 cylinder glow plug.
Funnily, I wiggled the wire where it connects to the plug, and so far it's stayed off.
But, when the glow plug code was thrown, the dash also showed: "Emissions Workshop", which went away when I cleared the P0671 code.
Does a glow plug code trigger the Emissions Workshop warning?
Thanks, Dave.

There are a bunch of text warnings the MFA cluster is able to display depending on what faults are being flagged. So yes, any engine/trans fault will trigger the "emissions workshop" warning. There are others, related to brakes, oil pressure, coolant temp, etc. It is just an extra convenience, nothing more, no need to overthink that part.
 
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