2008 V70 gas gauge problems

[halseyfolk]

Bought a used '08 Volvo V70 last year, and we've had several distinct-but-possibly-related problems with the (digital) gas gauge.

Problem 1: Quirky gas gauge and unable to completely fill gas tank) From the beginning, we have never been able to get a "full" tank of gas in the car.. at least not according to the fuel gauge. The auto shut-off at gas pumps would trip - and even after anywhere from 1 to 3 attempts to "top off" - and the gauge would typically read in the neighborhood of ~5/6 to ~7/8 of a tank. Rough estimate: the most we've ever been able to put into a nominally practically empty tank is 14-15 gallons (may not be quite right... this guess is with the belief that the tank is ~18 gallons... without numbers what I'm trying to say is that we've never seemed able to actually put a full-tank worth of fuel into a nearly-empty tank).

Also, the gauge reading always seemed pretty quirky - over the course of relatively short distances the reading could drift up or down by 1/8 (sometimes reading full but almost never right after filling up). Overall, though, it gave what seemed to be a pretty good sense of how much fuel was in the tank.

Problem 2: Failed gas gauge) We set out on a long trip, and the gauge has "drifted" up and reads full. 45 minutes of driving and the car stalls out. Upon getting it towed back to town and to our mechanic, they inform us that the tank is empty... So our quirky gauge is now just wrong (stuck high)...

Mechanic recommends new fuel pump (OEM) which will also bring a new fuel level sending unit. Out of the shop, fill it up, and the gauge stays stuck high. Back into the shop. Mechanic tells when picking up that there are hoses that are loose and free floating in the gas tank and that the float arm got ensnared. They rerouted the hoses to ensure that a snag doesn't happen again. Fill it up and start on a trip.... reads full for 100 miles... We take it back in, they warranty the fuel pump and get another new one and put it in, and they do everything they can to ensure that the float isn't getting snagged in anything. Still broken. Then, we try something different - we replace the Pump Electronic Module (PEM). Still broken.

We have been driving it around for a while now (~2 months) and just fill up based on the odometer - once our trip ODO reaches ~200 mi. The gauge reads full ~90% of the time, what might be in the neighborhood of "correct" ~5% of the time and whatever the heck it wants to the other 5%.

To take another crack at it our mechanic is recommending a new fuel tank... Does anyone have any other good ideas?

[halseyfolk]

Whoops! I meant to post some links to other things I found... but essentially Googling "2008 volvo v70 gas tank won't fill" and "2008 volvo v70 faulty gas gauge" return some similar sounding results to my problems, but I have not been able to uncover anything that I've found useful or definitive.

Edit
I'll try and update this list as I go, but thought it could be useful to cross list other posts that sound similar as I continue to poke around.

Problem 1 - Unable to fill fuel tank all the way
- Gas Pump Keeps Stopping When Getting Gas: viewtopic.php?t=92810 (this post if for a P2 and ours is P3 though.. I think the fuel tanks and all are quite different)

Problem 2 - Faulty gas gauge
- 2008 XC70 Apparent misleading reading on fuel gage: viewtopic.php?p=313203&hilit=fuel#p313203
- Gas Gauge Isn't Working: viewtopic.php?p=480275&hilit=fuel#p480275

Other Related?
- 2008 V70 P0190 Fuel Pressure Sensor: viewtopic.php?p=329071&hilit=fuel#p329071 (though we never got any kind of check engine code)
- Fuel pump failure P3 D5 S60: https://ozvolvo.org/discussion/11199/p3 ... mp-failure