Replacing fuel temp sensor, tutorial

McBrew

Top Post Dawg
Joined
Oct 30, 2002
Location
Annapolis, MD
TDI
2003 Golf GLS TDI, 5 speed, Silver/Grey
In hopes to cure the "Quantity Adjuster - Upper Limit Reached" CEL I've been getting from time to time, I've just replaced the fuel temperature sensor. The sensor resides just under the cover of the fuel injection pump. Although one special tool is required, the job is quite simple.

Tools required:

10mm nut driver (or socket) to remove engine cover
3/8" ratchet handle
5" (at least) extension
TX30 socket (male, non security or security)
TX10 socket (male, non security or security)
13mm socket
MetalNerd injection pump tool
1 wire-tie (optional, but recommended)
some rags

Part required:

Fuel Temperature Sensor VW part no. 028 906 040 C


After removing the engine cover, you'll need to remove the injection pump cover. FIRST, place a wad of rags in front of the injection pump to catch the diesel fuel that spills out. These bolts are not very tight... even a 1/4" ratchet will remove them easily. Use a TX30 bit to remove three of the bolts. Use a 13mm socket on the DieselGeek adapter to remove the triangle bolt. Now the top will remove, and some fuel will spill out.


Use a wire-tie to secure the cover and keep it out of the way. I used a clean rag to soak up some of the diesel fuel around the sensor. Note the position of the sensor. It looks like it could be installed upside-down, which may or may not affect it's operation.


Use a TX10 bit to remove the two screws holding the sensor. This could easily be done with a nut driver, as they are not especially tight. Remove the sensor, then follow the instructions in reverse to finish the job. Use a clean rag to wipe off the mating surface between the cover and the body of the injection pump.

After the install, my car started up without a hitch. During the initial test drive, I'd swear my car's performance is up a bit. Probably back up to what it used to be. Maybe the failing temperature sensor was acting exactly opposite of a tuning box or Evry mod.

Sorry, I don't have exact torque specs for the bolts. I put them back on about as tight as they were. They were not very tight at all. Of course, I tightened them in a cross pattern, to help it seat properly and evenly.

I'm sure someone around here has the proper torque specs...

-Jesse
 

DLV

Veteran Member
Joined
Dec 13, 2001
Location
Woodbury, CT
TDI
2002 Jetta TDI ALH 5M silver, 2011 Audi A3 TDI Monza Silver
Nice job! I'll be sureto save this one. Thanks
 

McBrew

Top Post Dawg
Joined
Oct 30, 2002
Location
Annapolis, MD
TDI
2003 Golf GLS TDI, 5 speed, Silver/Grey
VF, yes... too early to tell. I've gotten the CEL three times since December. Only time will tell. Like I said, though, I'm pretty sure the car was a little zippier... not like a bad MAF, but a slight improvement.
 

brenner

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Joined
Aug 1, 2003
Location
british columbia,canada
TDI
1960 mercedes benz 180db2001 jetta gls tdi silver,2000 golf gls tdi,2002 dodge 3/4 cummins ho souped up
like your post .did you buy the sensor from a vw dealer? what is the cost of a temp. sensor? thanks for the great tutorial!!
 

Denis

Veteran Member
Joined
Jan 27, 2002
Location
San Diego CA
TDI
Golf GL 5sp, 2002, White
Nice write-up, is there a gasket for the pump cover? If so is it available from VW or is it a Bosch thing?

Denis
 

MOGolf

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Joined
Jun 27, 2001
Location
underneath something
TDI
2001 Golf GLS TDI Reflex silver, rough road suspension and steel skid plate, 2004 Passat Variant, Candy White, rough road suspension and geared balanced shaft module, and much, much more. 2016 LR RR HSE TD6, 2019 Jaguar I-PACE
[ QUOTE ]
Nice write-up, is there a gasket for the pump cover? If so is it available from VW or is it a Bosch thing?

Denis

[/ QUOTE ]028 130 717 A
 

MITBeta

Top Post Dawg
Joined
Feb 24, 2001
Location
Boston's Metro South-West
TDI
2001 Jetta TDI, 2004 Sprinter CDI Passenger (Mid/High), former: 1996 Passat TDI Variant
[ QUOTE ]
I bought it from a VW dealership for ~$36.00

[/ QUOTE ]

D'oh... Impex had it for $17 when I needed one...
 

McBrew

Top Post Dawg
Joined
Oct 30, 2002
Location
Annapolis, MD
TDI
2003 Golf GLS TDI, 5 speed, Silver/Grey
[ QUOTE ]
D'oh... Impex had it for $17 when I needed one...

[/ QUOTE ]

Don't tell me that!!! /images/graemlins/crazy.gif

Oh, well... I was up there anyway... I bought 12 liters of VW505.01 oil for less than $70.00. So I didn't get totally ripped off!
 

golfstream

Top Post Dawg
Joined
Jan 10, 2001
Location
Balmer, Hon
TDI
Golf, 2000, Black
Nice write up and pics, McBrew.

I'd also like the answer to Denis' question... is there a replaceable gasket (perhaps o-ring style) for the pump cover?

Mel
 

MITBeta

Top Post Dawg
Joined
Feb 24, 2001
Location
Boston's Metro South-West
TDI
2001 Jetta TDI, 2004 Sprinter CDI Passenger (Mid/High), former: 1996 Passat TDI Variant
[ QUOTE ]
Don't tell me that!!!

[/ QUOTE ]

Okay, I won't. /images/graemlins/laugh.gif
 

LarryLymb

Veteran Member
Joined
Apr 13, 2002
Location
Lehigh Acres, FL
TDI
Jetta TDI Wagon 2003 Mojave Beige, 5 speed
Nice posting, McBrew. My fuel temp sensor went out and the dealer replaced the injector pump under warranty. Did you try this?
 

McBrew

Top Post Dawg
Joined
Oct 30, 2002
Location
Annapolis, MD
TDI
2003 Golf GLS TDI, 5 speed, Silver/Grey
Denis/golfstream, There is a rubber gasket set into the cover. From what I understand, it does not need to be replaced. 500 miles later, I have no leaking. This does not appear to be a high pressure area of the pump. The cover bolts were not very tight... I believe they could have been removed with a nut driver.

wingnut, go for it!

Larry, I probably could have had it replaced under warranty... but I would rather replace a $36 part myself than have VW mechanics removing and replacing my injection pump. My timing is good right now... I don't want them messing that up. I would also rather not be without my car for that long... it took three trips to the dealership to get my seat latch fixed /images/graemlins/crazy.gif.
 
G

gboss

Guest
[ QUOTE ]
Nice posting, McBrew. My fuel temp sensor went out and the dealer replaced the injector pump under warranty. Did you try this?

[/ QUOTE ]

Wow! nothing like replacing a $1200 part for a failing $36 part! What the hell is wrong with this picture?!
 

LarryLymb

Veteran Member
Joined
Apr 13, 2002
Location
Lehigh Acres, FL
TDI
Jetta TDI Wagon 2003 Mojave Beige, 5 speed
Borsch wanted the injector pump back so they could find out why the fuel sensors were failing. I showed up unannounced at 9AM and was out of the dealer at 12. VW of Fort Myers did the work. Let's give credit where credit is due!
 

Gigitt

Veteran Member
Joined
Jul 12, 2002
Location
Australia
TDI
2011 Mk5 Jetta 125TDI, 1996 Mk3 Golf TDI
Nice write up... about to do my A3.

So can you do this with a warm engine or should it be done with a cold engine?
 

dkuster

Veteran Member
Joined
Jan 5, 2003
Location
Washington, NJ
TDI
'03 Golf GLS TDI
Couple of quick questions:

Other than the cell you got, what are the symptoms of
a bad temp sensor? Is hard starting one of them? I've
been having consistent hard starts for several months
now.

Is there a way to check the proper function of this sensor
with vag-com?

When you were done, did you have to loosen an injector
nut and bleed the system?

Thanks!
 

Gigitt

Veteran Member
Joined
Jul 12, 2002
Location
Australia
TDI
2011 Mk5 Jetta 125TDI, 1996 Mk3 Golf TDI
To answer my last question... I did let the car sit for 2.5 hours before taking the pump top off... the engine was warm.

I don't have CEL in my Mk3 - so cannot answer.

As the car was probably running for like 3 years without the temp sensor I did not notice anything about the engine. Then again I do not have freezing temps here in winter!

I did notice more the fuel quality did play a part is how the car performed.

Since doing replcaing the temp sensor I have notices these improvements - note these were instant improvements!!!:
1) Starting is smoother.
2) Engine sounds under less strain while driving.
3) Less engine noise - clunkiness has gone.
4) seems to like reving again.
5) Shutdown is smoother - no shudder... althought I did have 2-3 shakes/shudders before - which is pretty normal I thought for a diesel (Like my old Mk1, my Dads LandRover Defender TDi, and out Farm Tractor)
6) Much more Power!!! - OMG... like it has been chipped.
I cannot beleive that I did not notice the temp sensor dying. Car was Instantly improved!

I just took the top off, swaped over the sensor, did some major rust cleaning with a old toothbrush
(i have a pic of the rust I'll post up later), cleaned and wiped with diesel soaked paper towel the mounting flanges and inside the top casing. Then I just poped the top back on and screwed it down firmly.
I did not have to touch the injector lines.
I did not have to bleed the pump or lines.
Car started 1st go. I did not have to crank it. Just turned to start and she fired up straight away. There was no hesitation or any symptoms like air in the lines.
No leaks.

Let the car warm up for about 20 minutes reving the engine every so often to about 2000... tested with VAG-COM TDi Timing and it was spot on... values @135 fuel temp were between 41-43 sometime diping to 39 and hitting 44.

One big point I have to make!
As my pump showed signs or water in the diesel as the pumps nuts and bolts have rust... even the tiny temp sensor screws had rusty heads... be careful with the screws taking them out and putting them back in. I think I stripped one of the the temp sensor screw head while putting it back... so I figure.. next time I have to do it I will get some replacemnet screws...

Anyone know the part No. for replacement Temp Sensor Screws?

Edit: Yuk!
 

DeafBug

Gone but Never Forgotten: Requiescat In Pace
Joined
Sep 22, 2000
Location
Twin Cities in MN
TDI
2001 NB
Just one thought about removing the pump cover. Isn't that similar to doing a hammer mod? What is the relation or difference between sliding the fuel cover a hair bit versus removing it and replacing it back exactly where it is? Or does the hammer mod move a different part?
 

dkuster

Veteran Member
Joined
Jan 5, 2003
Location
Washington, NJ
TDI
'03 Golf GLS TDI
The fuel pump is a "sandwich" of three, stacked sections.
With the hammer mod you are moving the middle section in
relation to the other two. So, just removing and replacing
the upper piece won't mess with your IQ.
 

mojogoes

Top Post Dawg
Joined
May 1, 2003
Location
england
TDI
mk3 tdi golf
No the G62 is the coolant temp sensor which is located at the engine block and some times shows up a fault on the temp heat dile in the car as a low reading.
The sensor talked about here is in the top of the fuel pump.
Gigitt.......is your car an A4 and if so how many miles on her and is it the same part number as for the a3's, do you think its condusive to how many miles you have on your car and do you think it would be worth while changing it if say like me with 145,000 miles and never been changed ..cheers
 

mkosem

Veteran Member
Joined
Jun 27, 2003
Location
OH, US
TDI
2001 Golf TDi
I've got the Quantity Adjuster - Upper Limit Reached CEL, and have had a bit of white smoke on startup recently. The third pic in the thread is dead. Does anyone happen to have it? If not, is it a simple task of unscrewing the torx screws, removing the sensor, and reinstalling?

--Matt
 
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