Injection pump is on fire

Tmorgan1988

Member
Joined
Aug 11, 2017
Location
Colorado
TDI
2001 Jetta tdi
Hello I am new to the club, I have used many threads on here to work on my recently purchased 2001 Jetta tdi! I did the 5 speed swap and it worked great, I started to drive and I felt under powered. I found another thread and changed my in tank unit (it was clogged just filthy) changed fuel filter fuel flows freely now! Injection pump still gets extremely hot to the touch! Is it burnt up by previous owner? In my vcds jetta timing my fuel temp gets up to 200 before I get scared and shut it off! What do I do? Any other causes or fixes before buying a 1000 dollar injection pump!
 

burn_your_money

Veteran Member
Joined
Oct 16, 2012
Location
Missouri
TDI
99 Beetle, 96 B4V, 05 Passat wagon
Is your fuel filter getting this hot as well? How about the fuel return lines? If you remove the return line from the pump with the car running does fuel come out? It's a tiny little return hole and it may be clogged. I'm pretty sure there is a piston and spring in the return fitting as well. That may be seized in place limiting fuel flow. The fuel flow is suppose to cool the pump.
 

Tmorgan1988

Member
Joined
Aug 11, 2017
Location
Colorado
TDI
2001 Jetta tdi
Burn your money thanks for the reply, I did fill a water bottle with diesel and put both lines in it it seems to be pushing plenty of return fuel back into the bottle I'm wondering if the clogged in tank unit from before fried my injection pump, I would add the photos but don't know how, the engine also runs fine while driving but when I pop it out of gear and let it idle down the engine shakes and it won't idle, smooth.
 

burn_your_money

Veteran Member
Joined
Oct 16, 2012
Location
Missouri
TDI
99 Beetle, 96 B4V, 05 Passat wagon
Are you able to hook the fuel lines up so that you are only using a jerry can for supply and return? Put more than enough fuel in it so you can drive it long enough to get up to 200F. You need extra fuel in the container to slow the fuel temp increase. That test will tell you if the issue is pump or fuel return/delivery related. You may just have a faulty thermo valve on the fuel pump. As a different test you could bypass it using a barb fitting for the lines and a loop of hose on both ends of the thermo valve.

Have you confirmed that the fuel temp sensor is reading correctly by taking a reading of the coolant, fuel and ambient sensors on a cold not running engine?

I know when these pumps are being calibrated on the test bench they are tested at 140*F. You're obviously a good ways over that.
 

Tmorgan1988

Member
Joined
Aug 11, 2017
Location
Colorado
TDI
2001 Jetta tdi
No I have not done that, is it done through vcds? I would like to try that tomorrow, it is done while the engine is off?
 

burn_your_money

Veteran Member
Joined
Oct 16, 2012
Location
Missouri
TDI
99 Beetle, 96 B4V, 05 Passat wagon
The sensor test is done with VCDS with key on, engine off. All the sensors should be within a couple degrees of each other.
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
There's a thermostatic tee on the filter that recircs fuel until it warms up then sends it back to the tank.

Check that you have flow from that point back to the tank. If it's working properly drive more and worry less. The pump's sitting next to a hot engine and doing a lot of work. It gets hot.

Please start only one thread on a subject. Especially when people are responding to the first one.
 

Tmorgan1988

Member
Joined
Aug 11, 2017
Location
Colorado
TDI
2001 Jetta tdi
Ok thanks klxd, appreciate the help, I was just worried because my neighbor has the same year Jetta and his pump stays cool after a 150 mile trip, mine gets to 200 after driving it around the block. I'll do all the recommended tests by you guys and let ya know. Thanks for the help and guidance!
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Ditto what KLXD said.... Sounds like the Thermo T is malfunctioning causing the return fuel to re-circulate at the filter, thus allowing heat to build.

I'd venture to say that the IP will run a temp fairly close to the temp of the engine at full warm-up!
 

Tmorgan1988

Member
Joined
Aug 11, 2017
Location
Colorado
TDI
2001 Jetta tdi
Thanks to everyone for the help, it was the thermostatic t in the top of the fuel filter, the car now idles like a champ and the fuel temps dropped, not allot but 20 set is something! Thanks again
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Outstanding!
Fuel Temperature: 91 - 201 = 20 - 80 degrees C
That's 68 to 176 F (many of the VCDS readouts are unitless numbers).
When you get time run a can of Diesel Purge thru it, straight from the can. It could clean up the pump and injectors.
 
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