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Old 04-30-2018, 05:43 PM
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andrewwynn andrewwynn is offline
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Location: Racine, WI
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Gauge shows empty but engine is fuel starved and there is 20L in the tank.

So break it down to components:

I'm not sure if you were able to start up without issue but assuming also true:

1- if fuel starved with gas remaining means the siphon isn't working (if you can start when adding fuel)

2- if there is still fuel and the gauge reads zero there is *additionally* a problem with the float/sensor.

3- siphon not working is usually one of two things: weak electric pump or leaky "seal" going into the jet pump.

I would crack the seal on the left sender and raise it up a bit, put the key to the "run" position and look for leaks. Only lift it a crack I got sprayed pretty hard when I opened it 3/4"

If no spray it's either the pump or the FPR but if the FPR isn't retuning enough gas to siphon I would expect to see too high of pressure at the rail so that's another test you can do.

Use test six to determine the levels in the tank unfortunately you have to drive a good while to empty 96L but drive with test six going until the right side drops while the left side doesn't. Then you can determine if the problem is out of the normal.

If there is a plugged siphon foot for example the gas will dump through the pressure relief into the surge tank and you will effectively have a 5L gas tank.

If the relief valve is partly stuck open similarly you can get partial siphon. You can crack the seal on the right sender unit and observe the overflow valve to determine if gas is coming out.

My right float is getting caught and gets stuck about 3.5L from zero it's annoying because it throws off my DTE by 20 miles I will fix that soon with photos and add the appropriate feedback where it belongs
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