Volvo S40 2003 2.0L
So recently the car started to jerk while driving and idle badly and shutting down (also fuel meter didn't work after filling the tank and problems started after fueling)
then it started work again and i went to fill the tank and it started again so i changed the battery since that was advice what i got from another ppl (engine light disappeared and fuel meter started to work but always slowly went to full and showed the amount KM i could drive rising slowly max was 900km)
and car seemed to work fine and now today i went fuel it once again (since didn't know for sure how much there was) and it started to do it once again
Only codes what i get from OBD P0131 and P0138 (lamda sensors telling low and high voltage) and even these disappeared one point but now they back once again

I'am just wondering is the fault because the sensors or could it be something else? since it just happens when tank is full

TLDR
Car jerks and idles badly after filling the tank full
Car works normaly when tank isnt full

 

Did you "top off" the fuel tank after the automatic valve stopped pumping? That can flood the evaporative system, and cause problems (and I can believe, cause problems like you're seeing). Otherwise, I can't imagine what could change between a 100% (properly) full tank and one that's at 90%. Well, other than an intermittent fuel pump that's somehow affected by fuel level (very possible, I suppose). I'd suggest putting on a full-feature scan tool (like the Torque Pro app using an OBD bluetooth plugh-in module) to monitor fuel pressure to see if it's low when you're having problems. The fact that the fuel indicator seems to stop working when the fuel is totally full.

How far down do you have to get the fuel for the car to start working well again?

 

About 80% to half tank but the gas gauge still acts weird and shows full tanks tho and shows the KM wrong how long i can still drive
also i usually stop fueling when it stops automaticly and have done like that always also its winter time in here so i used some ice removal what maybe helped since tank is now full but haven't done the jerking this far. also for tested does it get air or not by leaving the fuel cap open so the tank gets air and then fully tight and there wasn't any effect so the tank gets air normally i believe ?
Also now having full tanks but gas gauge shows empty tank and that telling me to go fuell

Also sorry for typos

 

Could have been due to water (ice) in the system. I'm not sure why it would be worse with the tank full, but I suppose that's possible. Otherwise I'd suggest monitoring the fuel pressure when the car is running well, and when it's acting up. There are various ways to do that, but I use the Torque Pro app, which gives me access to the fuel pressure (or did, when I owned a Volvo V50).

 

I think the 03 S40 is prior to when Volvo when to the variable pressure fuel pump found on the Gen 2s. The wonky guage suggests the float is getting stuck or you may have a fuel pump or wiring issue. I agree with the suggestion that if your fuel pressure is wandering or off you'll see emissions fault codes for misfires or fuel trim (ie the O2 sensor can't correct enough so it goes out of range throwing the code). It does sound like the tank has a venting issue when full but again could be something within the pump. One thing to consider is measuring the pump's current draw to see if that's within spec.

 

Little update i replaced both lambda sensors and used ice remover on gas tank and the ice remover did help ? and haven't had the jerking etc after that. need still go to place get computer reset since some reason my obd reader dosnt do that or i dont do it right lol.

But gas gauge doesnt work still same with the estimated km i can drive it just shows empty all the time now and telling to fuell

 

BTW, the rear O2 sensor only measures cat efficiency - its the front that controls the fuel trim. O2 sensors get blamed for any fault code related to long term fuel trim issues so its likely you replaced parts that were good. If your tank always reads E, you should check the connections to the fuel pump assembly (which includes the sending unit - google "volvo 30630596" for a pic) including the ground to make sure the signal is getting to the dash. The sending unit's impedance can also be measured - just not sure what the value should be. You may need to pull the pump out to see if the float is bad or the arm is stuck...

 

Little update sensors changed and everything works fine else then the fuel meter showing empty always :P i am thinking that might be problem in floater or something ? but yeah

 

Congrats on getting the original problem fixed. And yeah, the fuel gauge problem is most likely the sending unit in the tank (since that's the most difficult to fix). ;-)

 

All fixed!!
the floater sensor's wiring was the problem the wire was badly soldered by old owner ? or just got loose from the soldering some reason?
quick soldering back together and the fuel meter worked again

 

Great a cheap fix