Hi,

What did they do to “fix” your xc60?

 

Not sure what was done. The tank was removed for the fix. They are going to try again - I'll pay more attention this time.

 

Thanks for chiming in with your gas tank experience. Do you have any update on the details of the work?

 

The Volvo agents assessed the problem and this time pointed to water in the tank - which was news to me/ no idea where that would have come from, and it didn't at all feel like this was the issue. But they showed a photograph of something they had removed from the bottom of the tank (presumably) that appeared to have water in it. Their recommendation was to remove the tank, clean it and replace the pump and seal, To me this doesn't at all equate to the problems I've seen. Most recently it has run out of gas going up long steep hills, while having petrol levels higher than where it runs out (early) on the flat. It has done this three times (ie run out going up a hill). I'm guessing this has something to do with remaining gas available on the pump side of the tank and heavy consumption - or perhaps water? After a while the car would eventually start and run normally (still facing up hill). It seems to me likely that whatever is balancing the petrol levels in the tank manages to bleed enough through to run again after a while, but doesn't have the ability to balance the sides when demand is high driving up the hill. So..... out with the tank etc I guess. Finding some way to check/clear the fuel balance system seems likely what is needed.
I was told my car was one of two with this problem recently worked on when originally serviced. I can't help but think Volvo know very well what this problem is - they just aren't advertising it. Seems to be the balance system. Haing said that they replaced th epump last ti,e amd it seemed to be fixed. Maybe they quietly flushed the tank / cleared the balance system at the same time? Who knows.

 

Here's an interesting explanation, at least to me, of how the fuel tank works. I got this from a Swedespeed thread which I've linked below.

"The tank has a raised center to clear exhaust and rear driveshaft on AWD models. The pump is on the RH side and the fuel goes from there to engine. The left side gets fuel sent to it and a venturi device (called an ejector pump but there are no moving parts) gets fuel spray across an opening and it picks up an fuel and dumps it into the fuel pump cup on RH side. Once fuel falls below about 1/2 gauge the fuel level on LH side will start falling and the RH side will stay the same untio enough fuel is consumed that there is no fuel to be picked up on LH side. If you were to go drive your car 50 miles and recheck the LH and RH fuel levels you'd see RH with 4 gallons and LH with 1 gallon or less. AT the point the LH side has no more fuel to pick then the RH side begins to drop below 4 gallons. Up to that point the fuel dumped on RH side spills over the hump".

https://www.swedespeed.com/threads/p...9#post-8217499

The advice my dad gave me years ago was to NEVER let the gas tank to below 1/4 full before refilling. This prevents any debris in the gas tank from clogging up the pump or fuel line. Secondly, NEVER over fill the gas tank. An excess flow of gas can ruin the charcoal cannister, which will then degrade engine performance.

PS: Suggest doing a search in the Swedespeed owner's forum. There are many threads on this topic.

 

Many thanks - that makes sense. Will check out the forum.
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Thanks for all the updates, @Murrayp . How has your car behaved since the service you mentioned?

Let's keep this thread active as more personal accounts continue to come in. Reading through the experience with Volvo technicians here, it seems that anytime the gas tank is removed for a suggested fix, the tank removal process temporarily fixes the problem. But still, we're not closer to a definitive answer.

I'm still baffled by the number of P3 AWD XC60s out there that don't seem to have this issue. I live in Bend, Oregon and they're everywhere. What bothers me the most is, with such a unique problem, we're stuck with car that's worth half its value on the used market, regardless of how well-maintained or well-optioned it is. I love driving this T6 with the Polestar tune on the 8-speed transmission, but this gas tank issue is always in the back of my head.