Over the past few weeks, I've discovered a few somewhat odd issues. The first is the car constantly throwing P2195 codes once my gas tank hits a little below the halfway mark. As soon as I fill it past the halfway mark, the light turns off, and the code doesn't appear.

I've had both A/F sensors replaced on two separate occasions. It fixes the issue for a few months, but the problem will arise again. I've taken it to two different shops and both have said (and replaced) the rear A/F sensor. Am I possibly just getting a bad batch?

Also, I have noticed lately that when I put the car in D, once I take my foot off the brake, the car will launch up to about 15 mph. It won't occur in 1, 2, or D3. There isn't an erratic idle, but the car is due for a fluid change. Could this be linked to low ATF?

 

The code means that the rear O2 sensor is stuck reading a lean condition. It may be the sensor is constantly detecting a lean condition and is actually working.

Do you have a scan tool that can read live engine data, or have access to one? You almost need that type of tool to start testing why it is stuck lean. I wouldn't replace the sensor again unless you do some testing.

You definitely want the proper fluid levels in your car. Check the ATF and oil level as described in the owner's manual. Low ATF could cause poor shifting, so check the fluid levels. It seems unlikely to cause the P2195 code, but definitely keep fluids at the proper level.

 

Thanks for the response! The only scan tool I have is the ELM 327 scanner with the Torque Lite app. The app does read real time data, but when I go to Autozone tomorrow I'll have them use an actual scan tool to see if it throws anything different.

 

Just an update. On my lunch break today, I took it to Autozone and they pulled the 2195 code, as well as P0171 which leads me to believe the system is in fact running lean. I'm guessing this could be a reason why I'm getting such poor gas mileage, and overall performance issues.

 

If you scan tool can read fuel trim, see if adding propane makes the car go rich. There is a youtube channel called schrodingers box that covers a lot of this stuff and can help a lot to diagnose engine performance issues.