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  #11  
Old 28th February 2020, 11:58 AM
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Originally Posted by moltuae View Post
...the workaround is to keep half a tank or more of fuel in the car at all times. I drove mine like that for a few years. It can be fixed but I think there's probably a knack to it. After a few failed attempts (by myself and 2 different mechanics) I just gave up and replaced the entire tank.
This mirrors my experience exactly. Fuel gauge was on the 3rd segment (out of 12, I think) when she ran out of fuel, so probably around 50-60 miles of range showing. Fuel pump replaced and subsequent return trips to the garage for new seal kit and re-seat. Still runs out of fuel at the 3rd segment but I'm used to that by now. Not prepared to spend any more money on that particular problem.

New fuel pump is slightly more buzzy than before and you should be able to hear it prime when turning the key to ignition on.

Hope you get your problem sorted.
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  #12  
Old 28th February 2020, 12:17 PM
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Just to add some background info:

Mine was a combination of two isssues, namely fuel pump failure and then the subsequent problem of 'running out of fuel' when the gauge shows a quarter full. Once the fuel pump was replaced, and having effectively run out of petrol, the car showed signs of attempting to start on a couple of occasions and then pretty much nothing else. Strong cranking from the battery/starter motor. Low-loaded back to the garage to check (I was convinced there was fuel in there) and then discovered thanks to this forum about the fuel tank issue where part of the system to maintain equal levels on both sides of the fuel tank isn't working properly in my case. MJ seems to think it's one of the fuel return pipes possibly being blocked.

When my fuel pump borked, there were no prior warning signs apart from the car not moving lol, just a couple of spurts forward before the car stalled in the middle of a nicely-painted diagonal striped box junction.

Good luck with your investigations. It's probably worth updating your profile/signature to reflect where you are geographically, as someone on the forum may be able to assist with a quick VAGCOM or OBDEleven unit.
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  #13  
Old 28th February 2020, 12:42 PM
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It's probably worth updating your profile/signature to reflect where you are geographically, as someone on the forum may be able to assist with a quick VAGCOM or OBDEleven unit.
Done! Thanks for the tip

Marty! You visiting Newcastle, NSW anytime soon? If so, bring your Vag Com cable and working laptop please!
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Last edited by C4R 100N; 28th February 2020 at 01:12 PM. Reason: Marty not Matty, doh!
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Old 28th February 2020, 01:20 PM
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Also worth considering crankshaft position sensor, which recently went on mine. We thought it was fuel pump and got it recovered, changed the fuel pump, seemed to fix it and then it went wrong again and did the same thing, but that pulled a code which gave it away so do scan the car before you try anything else!
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  #15  
Old 28th February 2020, 01:49 PM
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Originally Posted by Architex_mA8tey View Post
Also worth considering crankshaft position sensor, which recently went on mine. We thought it was fuel pump and got it recovered, changed the fuel pump, seemed to fix it and then it went wrong again and did the same thing, but that pulled a code which gave it away so do scan the car before you try anything else!
Thank you! I do intend to scan as soon as I am able. I posted a question in the Vag Com section and would appreciate any input on that if anyone has an idea. Thank you lovely people!

can I do this?
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Old 29th February 2020, 03:42 AM
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Default ***UPDATE*** Starting Fluid allows the car to start momentarily.

Updating this thread to report some progress in my diagnostics of this starting problem.

Spraying starting fluid into the hard plastic black duct attached to the air intake allows the car to start and run briefly. It runs as long as I continue spraying the ether into the duct.

So that points to no fuel delivery. I cannot hear any noise from the fuel pump assembly when turning the key to accessories on, nor when cranking the engine. I am guessing then that either the fuel pump is gone or there is no power getting to the fuel pump.

Please advise how I can move forward from here.

Check fuse? (Where is it?)

Fuel pump relay? (Where is it? how could i test it?)


Bang on fuel tank from underneath with rubber mallet? (Don't bother?)

use multimeter on connections to fuel pump assembly to check for power? (Which wires/terminals? Are there only two?)



Something else? (Suggestions?)


I am not trying to be lazy here in asking for help from you good people, but I know someone here will have answers. I will try to find out answers to these questions but will take me some time.

Will a scan be likely to give any pointers at this stage?

Any help that you can afford me will, as always, be most gratefully received.

Thanks,

Paul
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Old 29th February 2020, 07:36 AM
ainarssems ainarssems is offline
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Fuse locations





There is a relay somewhere but not sure which one it is.

Fuel pump is on the right side in the boot. Lift the carpet and remove the metal cover. There are more wires there as you have wires for level sensor as well. I don't remember wire colours but it's fairly obvious which are for the pump as the sensor wires are smaller/thinner. You can test the voltage at these wires with mulitimeter or test light. Pump is powered only for a second or 2 when you switch on ignition, while starting and when engine is running so it's a 2 man job to test - one checking for power while the other switch on ignittion.
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  #18  
Old 29th February 2020, 08:34 AM
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The relay is in the relay panel in the passenger footwell, in the bottom row. Not sure which one it is, but failure is rare compared to the pump itself. With the carpet up you should hear it click on and off when you turn the ignition on.

It probably is worth giving it a thump on the bottom of the tank to see if that does anything. Its not going to make it any worse
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Old 1st March 2020, 01:17 AM
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Quote:
Originally Posted by ainarssems View Post
Fuse locations





There is a relay somewhere but not sure which one it is.

Fuel pump is on the right side in the boot. Lift the carpet and remove the metal cover. There are more wires there as you have wires for level sensor as well. I don't remember wire colours but it's fairly obvious which are for the pump as the sensor wires are smaller/thinner. You can test the voltage at these wires with mulitimeter or test light. Pump is powered only for a second or 2 when you switch on ignition, while starting and when engine is running so it's a 2 man job to test - one checking for power while the other switch on ignittion.
Thanks very much for posting the decal as mine is missing when I just went to look

DARN! After double checking with ELSAWIN against the decal you posted it seems that someone has installed an incorrect fuse in position 1 of the blue(ST4) fuse carrier. The fuse is OK but it is 20A. Could that have led to the fuel pump burning out or something I wonder? Just off to check for power at the pump now

Quote:
Originally Posted by MikkiJayne View Post
The relay is in the relay panel in the passenger footwell, in the bottom row. Not sure which one it is, but failure is rare compared to the pump itself. With the carpet up you should hear it click on and off when you turn the ignition on.


It probably is worth giving it a thump on the bottom of the tank to see if that does anything. Its not going to make it any worse
Found the relay - position 6. It clicks when ignition turns on and I can feel that with my finger.

No clicks from the pump or any other noise when ignition turned on or when cranking.
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  #20  
Old 1st March 2020, 09:15 AM
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DARN! .... Just off to check for power at the pump now
I have 12 volts at the fuel pump for a second or two when the ignition turns on. So that is shaping up to be more likely than not, a bad/stuck fuel pump.

What is there left for me to do?

I have read that I might be able to 'hot wire' the fuel pump and even perhaps reverse the polarity momentarily on the pump to shock it into life.


The car is parked across the road which is not ideal. I would really like/prefer to be able to drive it back on my lot so that I can repair it and it is not out in the elements. We have had bad hailstones here lately.

I am tempted to do something like this to get it across the road:

https://youtu.be/v3orW5pfODo?t=535

OR THIS?

https://youtu.be/vZxtDY1A9-Y

Doable?!
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