Replacing PD Camshaft Position Sensor

dschultz

Well-known member
Joined
Mar 8, 2005
Location
Virginia
TDI
2005 Jetta Wagon
What is the procedure for replacing the camshaft position sensor on the PD?
I have a 2005 Jetta; Timing belt and water pump replaced 20,000 miles ago.

Can the sensor be accessed without removing the engine mounts and raising up the engine?

Also, is there a way to test the sensor with a meter? VCDS is reporting a camshaft position implausible signal - intermittent.

Dave
 

pruzink

Veteran Member
Joined
Sep 25, 2004
Location
Granbury, Texas
TDI
GLS, 2004, silver
Other than VCDS reporting this code, is there any other reason that you want to replace this sensor? The only thing that the ECU uses this sensor for is when starting the engine to determine which cylinder is going into compression so it can inject that cylinder 1st. Are you having any issues other than the code being in.
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
If what you say is true, prusink, I've got a problem. We have a customer that came in yesterday whose car has an intermittent cam position sensor code 'open or short to ground circuit' for a BEW. The VCDS/ Engine module/ Block 4 reading for the cam position is set at +.5. However, when the code pops up, the cam position sensor defaults to 0.0.

If the cam sensor means nothing after the car starts, try unplugging the cam sensor while the car is running... car dies.edit correction...if the CRANK SENSOR is unplugged, the engine won't start.

I believe the cam position sensor is CONSTANTLY reading the cam position, just like it's reading the injector balance; from idle clear through maximum rpm. If your cam sensor is giving a 'no read', I am sure you will be losing substantial fuel economy.

As for removing the sensor, first be aware that the 'no read' may have to do with a Service Bulletin that concerns the ground wire for the cam sensor. The wire may not be grounding correctly. The fix is to cut the ground wire and attach it to an access point close to the plug-in. There is a bolt that we attach the wire to that holds the water pipe across the front of the block.

If you choose to remove the sensor, you have to remove the timing belt, pulley, and some screws that hold the timing belt backing plate to the cylinder head. It's very close to remove the cam sensor, but it's doable. Make sure the sensor is bad before you bother taking it out. They don't often fail. editas oldpoopie points out in later post, the sensor can be removed w/o removing the timing belt.

The other thing to check is that the 'fingers' of the cam sensor wheel are not bent. If you have erratic distances between the cam sensor and the fingers, you can get a bad read.
 
Last edited:

dschultz

Well-known member
Joined
Mar 8, 2005
Location
Virginia
TDI
2005 Jetta Wagon
The economy is OK.

The issue has been long crank times when warm. (10-25 seconds!)

I had a Guru look at it with VCDS and we noticed the Camshaft position sensor intermittent.

Can you post or send me the service bulletin that reference the ground wire?

Think there are three wires going to the sensor; what one is ground?

Should I remove the battery and tray and check the grounds under there?
 

D-Cell_Mekanick

Veteran Member
Joined
May 23, 2009
Location
Sandwich, IL
TDI
2015 Honda Civic SE
The economy is OK.
The issue has been long crank times when warm. (10-25 seconds!)
I had a Guru look at it with VCDS and we noticed the Camshaft position sensor intermittent.
Can you post or send me the service bulletin that reference the ground wire?
Think there are three wires going to the sensor; what one is ground?
Should I remove the battery and tray and check the grounds under there?
I have a similar issue with my BRM. Long cranks on hot starts, normally 3-5 seconds to get it to fire and rpms are over 200 on the tach. I have found my engine harness to be worn in several places through the wire insulation. I have read that the cam sensor has fixed the long crank issue. But I want to replace the damaged harness first to see if that may be contributing to the issue. If not the new cam sensor will be installed in the future as well. My vehicle does not show any faults for cam position sensor though. Doubt anything I just said will help you, but you may want to check out the harness just to be on the safe side.
 

PDJetta

Top Post Dawg
Joined
Nov 6, 2003
Location
Northern Virginia
TDI
'04 Jetta GLS TDI Pumpe Duce Platinum Grey w/ Leather
The wiring could be bad, the camshaft position sensor could be bad, or its plug not seated. "Implausible signal" simply means its not being read and "intermittent" means just that, its sporatic. Try unplugging the sensor connector and plugging it in again. If that does not fix it, you're next step is either to replace the camshaft position sensor (if its not too expensive and fairly easy), or check for continuity from the sensor plug to the ECU, bearing in mind that even if the wiring shows continuity, there still could be a break. Wiggle the wirring while doing the continuity check to make sure its not intermittent.

--Nate
 
Last edited:

DPM

Top Post Dawg
Joined
Mar 16, 2001
Location
Newtownards, N. Ireland
TDI
2019 Rav4 AWD Hybrid, Citroen C4 BlueHDI
Unplugging a sensor completely is rather different to getting an unusual signal from it, Frank. Especially when it's a 3-wire device where the supply is being monitored...
 

GR40RCapri

Veteran Member
Joined
Jun 5, 2010
Location
MA
TDI
04 Jetta TDI 5spd auto
What was the outcome of your diag/assessment?? I'm having a similar issue... Intermittent/ no CPS signal... Although it recorded ~160 rpm during cranking.... Hmmm
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
If you choose to remove the sensor, you have to remove the timing belt, pulley, and some screws that hold the timing belt backing plate to the cylinder head. It's very close to remove the cam sensor, but it's doable. Make sure the sensor is bad before you bother taking it out. They don't often fail.

The other thing to check is that the 'fingers' of the cam sensor wheel are not bent. If you have erratic distances between the cam sensor and the fingers, you can get a bad read.
Not true, cam sensor is replaceable without disturbing the timing belt, cam pulley, or belt backing plate. I did one today....
 

GR40RCapri

Veteran Member
Joined
Jun 5, 2010
Location
MA
TDI
04 Jetta TDI 5spd auto
The wiring could be bad, the camshaft position sensor could be bad, or its plug not seated. "Implausible signal" simply means its not being read and "intermittent" means just that, its sporatic. Try unplugging the sensor connector and plugging it in again. If that does not fix it, you're next step is either to replace the camshaft position sensor (if its not too expensive and fairly easy), or check for continuity from the sensor plug to the ECU, bearing in mind that even if the wiring shows continuity, there still could be a break. Wiggle the wirring while doing the continuity check to make sure its not intermittent.

--Nate
Nate- (or all...)

What are the values we are supposed to be seeing??

And how to check/where is the sensor/plug?

I don't want to hi-jack the thread from the OP, yet, this might be some valuable info:

Member Ghaniba (MANY THANKS!!! Dave!!) :cool: Stopped by yesterday, and we took a peek as to why I have a MIL... appears to be a GP code (new plugs, dealer-destroyed GP ends on harness :mad: ) and a CPS code...

VCDS reads:


19463 - Camshaft Position Sensor (G40)
P3007 - 000 - No Signal
Freeze Frame:
RPM: 189 /min
Torque: 210.0 Nm
Speed: 0.0 km/h
Load: 0.0 %
Voltage: 8.51 V
Bin. Bits: 00001100
Idle Stabilization: 0.0°KW
(no units): 32.0


so, it seems that it sees Cranking, but? Maybe some of this discussion will help our OP..? :)


Not true, cam sensor is replaceable without disturbing the timing belt, cam pulley, or belt backing plate. I did one today....
how do we get to this guy if it's mounted to the cyl head... ? where is the connector?

thx J
 

lirunaway

Veteran Member
Joined
Feb 17, 2010
Location
Mooresville, NC
TDI
2006 VW Golf TDI, Model Year:2006 Code:6 MFG:07/05 Vin:9BWGR61J364004114 Sales Model:9B1 538 Description:1.9 TDI High 100 Engine:BEW Type:TD CCM:1896 KW:74 Description:Pumpe-D... Transmission:GPC Type:A Number:09AH GVWR:4097 Front:2269 Rear:1850
It has been a while since I replaced mine. It was difficult. I'm lucky I have long thin fingers. I believe I removed the timing belt cover and found the little black sensor. There is a little black oval plug I popped out to slip the sensor and wires through and popped back in place once complete. There was one little screw holding it in place that was hard to get to with the belt there, but I did it. My biggest problem was I was cheap. Instead of buying the OEM for $200.00, I bought a new aftermarket from RockAuto for $20.00. The old sensor wires came out the back at a 45 degree angle away from the engine nicely. The aftermarket sensor wires came out the back at a 45 degree angle towards the motor leaving zero clearance and barely possible to mount correctly. I ended up bending the wires as they came out to make it fit.
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
how do we get to this guy if it's mounted to the cyl head... ? where is the connector?

thx J

Remove timing belt cover, look slightly below and to the right of the cam pulley. Remove the one bolt fastening the sensor in place. Pop out the rubber plug in the backing plate, unclip the wire from the harness holder and disconnect the plug. Fish the sensor wire and plug thru the hole in the backing plate.

Fwiw the rubber plug can become dried out, brittle and break. Order a new one to be safe, part # is 1e0971904
 

Dimitri16V

Top Post Dawg
Joined
Jan 30, 2005
Location
DE
TDI
01 Golf, 04 Golf
that's what it looked to me, having an intermittent error with my camashaft sensor too. I did find out that if you clean the surface of it , the error goes away
 

jettasetta

Banned con artist and self-proclaimed victim
Joined
Mar 27, 2013
Location
San Diego
TDI
2005 Jetta GLS MK4 PD-BEW 5SP-EUH TDI
I just ran my first VCDS and got the same Implausible Signal - Intermittent Cam code as a mechanic who ran codes last month right after I bought the car. The car starts in 4 or 5 cranks with a substandard or under powered battery, no smoking and runs pretty good, but only gets 36.25 MPG (mostly hgwy).
This is the fault code that comes up:
1 Fault Found: 16725 - Camshaft Position Sensor (G40)
P0341 - 000 - Implausible Signal - Intermittent
Freeze Frame:
RPM: 2268 /min
Torque: 0.0 Nm
Speed: 102.0 km/h
Load: 0.0 %
Voltage: 13.60 V
Bin. Bits: 00001000
Idle Stabilization: 0.5°KW
(no units): 48.0
Readiness: 0 0 1 0 0
The mechanic wants to "set the timing" and install the roller/tensioner that wasn't changed when the belt was installed just before it was sold to me. As a newbie to TDI's I'm not sure what to make of the data in the error message. I don't have any cam or TB tools as of yet. Does the data imply anything meaningful to any of the experienced folks in here?
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
I have started my BEW with the cam sensor unplugged. It just takes a few more revs to start. Not sure why you had your experience Frank. The BEW can run on crank sensor alone. The BRM can run on either the crank or the cam sensor.

What can happen is if the Cam and crank sensor disagree, the ECU can get confused on the timing and refuse to run on either the BEW or the BRM. I have had one PD that would not start until I unplugged the cam sensor. Leaving it plugged in caused more problems.

Yes Poopie is right on changing out the sensor. It is a pain but can be done with the belt in place.

If the cam sensor and crank sensor disagree too much, and the ECU meets certain criteria (who knows how the logic is set up?) so it can tell which is in error, then it will change block 43 field 2 (torsion=cam to crank timing) to a default 0.0, throwing out the cam sensor input, and continue to run.

What really can foul it up is a constantly changing relationship between the crank and cam. One PD came to me barely limping along, running very poorly. The problem was excessive slack in the TB, causing rapidly and constantly varying relationships between the cam and crank.

So jettasetta, I would always replace the TB on a car I bought used, unless I knew for a fact that all the proper parts were replaced and knew the source of the parts, and who did the work. This just makes sense, to avoid a crashed head from a TB failure. I have had three cars come to me with very very cheap chinese copy timing belts on them, bought from prothe ( a very cheap parts place out of NC), one of these belts had broken in less than 10k, the others were very very close to breaking - badly cracked at each belt tooth.

In your case it is possible for this to also cause the code you are getting if there is slack in the TB.

This code is usually most likely from bad wiring, then bad sensors - either crank or cam, if the timing is properly set and the belt tight. In the ECUs logic the cause has been attributed to the cam sensor, but remember that it sees this as implausible because it compares it to the crank sensor.
 
Last edited:

pruzink

Veteran Member
Joined
Sep 25, 2004
Location
Granbury, Texas
TDI
GLS, 2004, silver
I have seen a few posts from people with BEWs that said the camshaft position sensor being bad would cause longer than typical cranking but once running the engine would continue to do so. I do know that without the crankshaft speed sensor the BEW engine will not run. I had an intermittent stalling issue on my 04 BEW Jetta mostly at idle that turned out to be a bad crankshaft speed sensor. The connectors for the 2 sensors (crankshaft & camshaft) are right next to each other. There is a posted repair in here on a grounding issue for the camshaft position sensor that invloves going under the cowl below the windshield wipers, removing the electrical harness from the ECU, removing the electrical insulation from this wiring harness, singling out one of the wires that goes to the camshaft sensor and then adding a separate ground wire to the harness (need to get an inexpensive test wire from VW to connect into the harness). Having played with trying to optimize my "torsion value" for improved fuel economy; I also know that adjusting this can create long cranking to start & rough idle. I also agree completely with Frank06's assesment (he has a thread tittles "the problem with setting torsion value")that the optimum value for this will vary from car to car.
 

jettasetta

Banned con artist and self-proclaimed victim
Joined
Mar 27, 2013
Location
San Diego
TDI
2005 Jetta GLS MK4 PD-BEW 5SP-EUH TDI
I have started my BEW with the cam sensor unplugged. It just takes a few more revs to start. Not sure why you had your experience Frank. The BEW can run on crank sensor alone. The BRM can run on either the crank or the cam sensor.

What can happen is if the Cam and crank sensor disagree, the ECU can get confused on the timing and refuse to run on either the BEW or the BRM. I have had one PD that would not start until I unplugged the cam sensor. Leaving it plugged in caused more problems.

Yes Poopie is right on changing out the sensor. It is a pain but can be done with the belt in place.

If the cam sensor and crank sensor disagree too much, and the ECU meets certain criteria (who knows how the logic is set up?) so it can tell which is in error, then it will change block 43 field 2 (torsion=cam to crank timing) to a default 0.0, throwing out the cam sensor input, and continue to run.

What really can foul it up is a constantly changing relationship between the crank and cam. One PD came to me barely limping along, running very poorly. The problem was excessive slack in the TB, causing rapidly and constantly varying relationships between the cam and crank.

So jettasetta, I would always replace the TB on a car I bought used, unless I knew for a fact that all the proper parts were replaced and knew the source of the parts, and who did the work. This just makes sense, to avoid a crashed head from a TB failure. I have had three cars come to me with very very cheap chinese copy timing belts on them, bought from prothe ( a very cheap parts place out of NC), one of these belts had broken in less than 10k, the others were very very close to breaking - badly cracked at each belt tooth.

In your case it is possible for this to also cause the code you are getting if there is slack in the TB.

This code is usually most likely from bad wiring, then bad sensors - either crank or cam, if the timing is properly set and the belt tight. In the ECUs logic the cause has been attributed to the cam sensor, but remember that it sees this as implausible because it compares it to the crank sensor.
Thanks for this help. Please excuse my delay. I checked for which belt was installed It looks to be a Gates T333. I may replace it when I to the roller and tensioner and one use bolts that were not replaced. I don't know which water pump was used, but the coolant looks orange. I would like to resolve the Cam sensor fault.
 

jettasetta

Banned con artist and self-proclaimed victim
Joined
Mar 27, 2013
Location
San Diego
TDI
2005 Jetta GLS MK4 PD-BEW 5SP-EUH TDI
There is a posted repair in here on a grounding issue for the camshaft position sensor that invloves going under the cowl below the windshield wipers, removing the electrical harness from the ECU, removing the electrical insulation from this wiring harness, singling out one of the wires that goes to the camshaft sensor and then adding a separate ground wire to the harness (need to get an inexpensive test wire from VW to connect into the harness).
I haven't spotted this guidance yet.
So it seems the 2004 was recalled, but not the 2005. It could be wiring or either the cam or crank sensor. Any way to tell which?
 

drywaller

Veteran Member
Joined
Mar 17, 2008
Location
USA
TDI
VDUBS
Have you figured out the issue with your cam sensor? Can anyone provide the link to the thread showing the procedure for grounding the cam sensor wire?
 

Herm TDI

Vendor
Joined
Nov 21, 2001
Location
Richmond, Maine...The far side of Witsend
TDI
2002 Golf GLS Malone Stage 3, P+520 nozzles, 11MM Inj pump, Sachs VR6 clutch, Stelth Race Pipe, Immo Deleat, EGR Deleat
A few words of caution on replacing the cam position sensor (CPS):
Once the TB cover is rempoved I would urge you to pack a few clean rags in and around the Timing Belt path. These rags will prevent the small CPS bolt from falling down into the TB path. Should you drop this bolt into the TB path it will take several hours of work to retreave it.
 
Last edited:

drywaller

Veteran Member
Joined
Mar 17, 2008
Location
USA
TDI
VDUBS
Thank you for the info.
How did you locate the faulty wire?
 
Last edited:

jettasetta

Banned con artist and self-proclaimed victim
Joined
Mar 27, 2013
Location
San Diego
TDI
2005 Jetta GLS MK4 PD-BEW 5SP-EUH TDI
Have you figured out the issue with your cam sensor? Can anyone provide the link to the thread showing the procedure for grounding the cam sensor wire?
No I had not and had to put this on the back burner because I've been having Laptop issues and do not have VCDS capability at the moment. Also, I went on vacation and have had to attend to completing AC repairs on my E36. Soon I am hoping to get my laptop and VCDS up and running so that I can return to the matter of addressing the TPS issue. To that end, you're reviving of this thread is certainly helpful and much appreciated. I'll be posting on my progress here once I can get back to it. Thanks again!


Additional thanks to Herm TDI as well for the guidance!


This group has made a huge difference in my ability navigate the TDI.
 

drywaller

Veteran Member
Joined
Mar 17, 2008
Location
USA
TDI
VDUBS
Jettasetta, I will be following along to see your progress. I also second that about this site. Without the help of members here I for one would be completely lost.
It is also much help for those of us that have (very) limited places to troubleshoot/wrench.
 

Dimitri16V

Top Post Dawg
Joined
Jan 30, 2005
Location
DE
TDI
01 Golf, 04 Golf
so what is the verdict on fixing the "implausible signal" error from the camshaft sensor ?

Replace the sensor ?
 

Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
If anyone wants a "how-to" for replacing the cam sensor, we have one here
Fixmyvw.com/how-to-change-a-g40-cam-position-sensor-10-minute-job/
Great write up, but it does look like you have a BEW, not a BRM like the OP was posting about. It would be great if you could indicate in your write up, exactly which engine it applies to.

I know both engines are very similar, but a newbie could be tripped up because he didn't know the write up he was working to isn't his exact engine.

Other than that, I really appreciate your commitment to the community. If it wasn't for Fred's, I would have probably destroyed my TDI a long time ago out of ignorance about these great cars "special needs".
 
Last edited:

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
so what is the verdict on fixing the "implausible signal" error from the camshaft sensor ?

Replace the sensor ?
You can get that same DTC from a cam that is more than 5 degrees out from the crank sensor.

So the first thing I would do was examine the TB. Is it tensioned? No fuzz? Cam sprocket bolts tight? Cam not all the way at the end of the slot (which may be normal, but may also indicate it slipped behind its three small bolts.)

The second would be to examine the wiring connections. Check the resistances of the plug and jack. The numbers are posted somewhere here on the site. Or PM me and I will measure them again on my BEW.

The third would be to mechanically check the timing. (Or simply try to adjust the cam no more than 5 degrees - not exceeding slot travel.)

Remember the cam to crank angle (MVB4 field 4) reads zero when the cam and crank sensors disagree - it is a substituted value.

On a BEW I would also remove and clean my crank sensor - make sure it did not get a piece of metal on it's tip.
 
Top