2003 Volkswagen Jetta Fuel gage at Half tank and car stalls

Tiny
VINMAN323
  • MEMBER
  • 2003 VOLKSWAGEN JETTA
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 83,000 MILES
My Jetta will sputter and sometimes stall when the fuel gage reads below half tank. I have used the mileage counter to see if the gage is not correct, but the level seems true. I would also measure fuel quantity by the amount going in on a refuel. There is no engine light. Again it only happens when fuel level is below half tank. Very Puzzled and wondering if you have any ideas?
Wednesday, August 19th, 2009 AT 4:47 PM

8 Replies

Tiny
DR LOOT
  • MECHANIC
  • 2,311 POSTS
I apologize for the late response, . I am in the process of moving to a different state am having a hard time. At any rate, have you ever had the fuel pump replaced? The reason I ask is because they may have not installed correctly, and there is a hose loose at the top of the pump, there should be an inspection cover that you can remove either in the trunk or under the back seat, and checked the pump hoses, make sure they are secure.
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Thursday, August 27th, 2009 AT 11:08 PM
Tiny
CHSCHAPIRA
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I see lots of posts on line regarding Jetta's having a fuel starvation issue when the fuel level reaches about 1/4 full or 3/4 empty, however you would like to look at the gauge. I to am experiencing this issue on my daughters cars, however only after she ran the car out of fuel. Will anyone confirm that their issue atarted after running the vehicle out of fuel?
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Saturday, August 18th, 2012 AT 7:26 PM
Tiny
EXOVCDS
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"Running out of fuel" should not cause any long term issues unless
the fuel pump is old and has lots of miles on it... at which point
the contacts of the brushes inside the pump become burnt, that then
leads to hard starting / no starts.

A quick and easy way to check for internal pump wear, is to do a
current ramping test... a good current pattern will be a series of
uniform humps with no drop-outs.

Sample: http://www.youtube.com/watch?v=7HHoDhR47ZI

If the vehicle always "acts-up" at a lower fuel level, then you
will have to remove the fuel pump and inspect the flexible plastic
tubes that route fuel in & out of the tank.

Using a scan tool such as VCDS, one can access the Instrument Cluster
Control Module to perform "output tests" of all the gauges.

If the gauge passes the output test, then you know that the problem
is either with the "sending unit" in the tank or the plastic tubes
on the pump.

Good luck,

Thomas
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+2
Saturday, August 18th, 2012 AT 8:24 PM
Tiny
EXOVCDS
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Sorry... the second link should have been to a picture of a pump assembly:

https://www.2carpros.com/images/external/1J0919087S-1.jpg

Thomas
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Saturday, August 18th, 2012 AT 8:26 PM
Tiny
CHSCHAPIRA
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The fuel pump was replaced in March of this year as the pump was experiencing a volume issue. The pressure was good, however the pump volume was low. Replacing the pump cured the lean condition code that would appear randomly.

I disconnected the fuel lines from the pump 30 minutes ago. When I disconnected the return line, air was being displaced from the fuel pump assembly. Could it have been that the reservoir was not full as the car sucked air into the fuel line when my daughter ran out of fuel?

I do understand from one of my local VW dealers that typically when someone runs a gasoline powered Jetta out of fuel it stores a DTC code. There were no DTC codes stored when it ran out of fuel or when it stalls.
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Saturday, August 18th, 2012 AT 8:45 PM
Tiny
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Codes are not always stored. "P0313 Misfire Detected Low Fuel
Level" is one example.

I didn't know the fuel pump was replaced. The pumps should be self
bleeding. I have installed many with an empty reservoir, with no
ill effects after.

Double check all the flex hoses for kinks or pin holes. That
would be my best guess at to the cause and would make sense that
air / vapour enters the system when the fuel level gets low.

You should have some kind of warranty on the pump. Should be at
least a 1 year warranty if new.

Thomas
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Saturday, August 18th, 2012 AT 9:19 PM
Tiny
CHSCHAPIRA
  • MEMBER
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Thomas, Thank you for being a sounding board. I too have replaced a couple of these stlye fuel pumps and the reservoir was dry when I installed the pump with no ill effects on a low fuel driveability issue.

After putting the sender back in the tank I test drove the car. The car was exhibiting the issue last night with approxiamtely a 1/4 tank remaining. After driving the car for about 30 miles with no issue, I removed the vent line again and this time there was no air being displaced into the fuel pump.

I am going to consider this a success today.

The real moral to the story is don't run out of fuel. The car was running fine until she ran out of fuel. The problem started immediately after that occurance.

Conrad
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Saturday, August 18th, 2012 AT 9:46 PM
Tiny
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Thank you for your follow-up!

I will keep your diagnosis / findings in mind for when I run into
something similar.

Thomas
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Saturday, August 18th, 2012 AT 9:53 PM

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