New fuel pump - now fuel gauge is erratic

[krenekj]

2002 V70 NA
160k mi

Indy shop replaced the fuel pump with a new Bosch unit. Now the fuel gauge generally reads a 1/2 tank low. So when it's filled up, it reads exactly 1/2. And when it's half full, it reads very close to empty. Sometimes it will kick up to the correct amount, but that is rare.

The shop will look at it when I get the car back (at college with the kids). Before taking it back I want to pinpoint the problem. I think either float sending unit may have failed. Assuming so,

1. Would the new Bosch fuel pump have come with a R float sending unit?

2. How do I test if it's the L or R sending unit? I cannot find a wiring diagram for the fuel level senders.

3. Is there anything else that could be causing this?

I will check the harness connections as well, but I'm assuming those are ok since most have clips holding them together.

Any help is appreciated.

Thanks.

[jonesg]

2002 V70 NA
160k mi

Indy shop replaced the fuel pump with a new Bosch unit. Now the fuel gauge generally reads a 1/2 tank low. So when it's filled up, it reads exactly 1/2. And when it's half full, it reads very close to empty. Sometimes it will kick up to the correct amount, but that is rare.

The shop will look at it when I get the car back (at college with the kids). Before taking it back I want to pinpoint the problem. I think either float sending unit may have failed. Assuming so,

1. Would the new Bosch fuel pump have come with a R float sending unit?

2. How do I test if it's the L or R sending unit? I cannot find a wiring diagram for the fuel level senders.

3. Is there anything else that could be causing this?

I will check the harness connections as well, but I'm assuming those are ok since most have clips holding them together.

Any help is appreciated.

Thanks.

The float pivots from rear to front of car.
If its slightly out of line it will give readings like that.
Installed one off kilter once, filled the tank for $5.
Loosen the lock ring and rotate pump.

[krenekj]

I had a look at VIDA earlier in the week and noted that both the left and right units need to be installed with an arrow pointed in a certain direction for accurate readings. I think this is what you are talking about.

I will check this when the car is back home in June.

Would a gauge that occasionally reads correctly only do so if both sending units were properly aligned?

Thank you.