CEL after low fuel light

[relwell]

First post, Great info on this board.

I recently purchased a 99 C280, 77,000 miles got the PPI from a local indie (used that as leverage with the dealer) had brakes and rotors done, trans fluid changed, oil change, new alternator (noisy). Rest of the car checked out good no codes at the inspection and it runs like a top. The CEL has come on twice, the first time after a fill up, I checked the cap and thought it was maybe a 1/8 turn loose. Tightened it up and the 3rd time I drove the car the CEL went out, just like the book says. Now today I drove about 10 miles with the low fuel light on and as I pulled into the gas station the CEL came on again. Should I pull the codes and try to trouble shoot it or is this common issue.

Thanks.

I "upgraded" from a 98 Ford Windstar. I LOVE this car.
I am no longer minivan man.

Richard.

[mbdoc]

All cars after 1997 have a system to monitor the fuel tank system for "vapor" leaks. You are having a problem with that system, have codes scanned from the computer. THEY will retrieve codes LIKE P0 442 or P0 455 or P0 460.
Let us know the code(s).

[relwell]

I ordered some code scanning software today, it should be here in a couple of days. I know I could go to AutoZone or the like and get the codes read, but hey I don't need much of an excuse to get a new tool. I'll post codes when I get the new toy.

Today on the third "driving cycle" after the light came on, it went out. Got to love consistent behavior.

Thanks.

Richard.

[relwell]

CEL came back on, this time not releated to the fuel level, I finally got the code scanner software today, fired it up and got the following codes;

P0161 Heated Oxygen Sensor Heater Circuit (bank 2, sensor 2)
P0156 HO2S Circuit Bank 2 Sensor 2

So, bad O2 sensor ? , which one is bank 2 sensor 2 ?

If it is a bad O2 sensor would it be prudent to replace all 4? (78K miles) Are they hard to change out ?

Thanks

Richard.

I Have A '99 E320 (august 1999 Production) And Too Am Receiving The Intermittent Cel For P0161 And P0156. No Noticeable Performance Or Gas Consumption Changes.
Would Appreciate If If Someone Could Answer Relwel's Queries ( I Too Have These Queries).
Also Please Advise For My Production Year, How Many Oxygen Sensors There Are And Where Are They Located.