1999 V70XC Fuel starvation with 15L remaining

[onefreehand]

I have a few fuel system problems and understanding if and how they are related could be the difference between fixing it myself or $2000 or so at the shop.

First, error codes. I am getting P0442 usually at the end of a pretty long monitor cycle. It's a minor EVAP leak. There is no fuel odor, and my gas mileage is good, so obviously it is indeed minor.
Could even be the gas cap - O ring looks bad but can't find a new OEM one. One mechanic had a quick look and said I needed new J hoses for the carbon canister though.

However, recently I was driving with a good 15L of fuel - not a lot, but 5L before the low fuel warning, and until now I have found this guage to be very accurate - I've driven over 50Km with the low fuel indicator on. Anyway - I ran out of fuel. Guage said about 15L - no indicator light. Just engine starvation.

Later I checked the code reader again and now it is showing a P0300 random misfire and the Volvo specific P1171.

SO, my first question is are the misfire and P1171 codes something you might expect after a fuel starvation stall? I have read that P1171 is usually a MAF sensor, but either way it relates to air/fuel delivery.

Second question - I have read that the V70XC has a lobed fuel tank design that requires a second fuel pump to equalize the halves. Could my running out of gas event mean that there is gas on one side of the tank, and not the other because that pump has failed?

Let me be clear - I am confident that there was still 15L of gas because I can easily track my fuel consumption with Volvo's wonderful guage that reads in Litres, rather than E to F, and I don't drive much. Furthermore, when I added 20 L, it read 35L. I am confident that the gas was in there.

So what is it? A failing fuel level sensor? If so, why does it appear to be reading correctly? A failing fuel pump? Why does it work fine when I have more in the tank?

If there is more going on than I think, then I will want to bring it to a shop so they can drop the tank and have a look at everything - the pump(s), EVAP system, sensors. If Anyone is confident it is one thing or another, I will try to fix it myself.

Thanks a lot for your help!

[scot850]

It could be your LH fuel pump has failed. I Volvos' wisdom, the tank needed to be split to allow for the rear prop-shaft to run through and the viscous coupling unit to be mounted.

One of the electrical guru's may be able to advise on how to test if the motor(s) are both working. If the LH one has failed (as I suspect), you then need to decide if you really need that 15l of fuel, or run with a smaller tank, especially if you don't drive much. I am in the process of pulling my V70R rear sub-frame, and I can assure you it has not been fun. You have to be able to drop the sub-frame to drop the fuel tank to access the fuel pumps which are mounted at the front of the fuel tank. The dealer quoted my a minimum of 10 hours for the job and parts, which would effectively write-off most P80 AWD Volvos. The other option is to cut through the rear floor, replace the fuel pump, and re-weld the floor back in.

Neil.