Can bad gas cause the check engine light to come on?

[Jersey General]

Yesterday my check engine light came on for the first time. I recently filled up with Mobil Premium Unleaded. I always use Shell gas, but since I was getting low on fuel I didn't want to chance making it to my regular Shell station. The car took just over 16 gallons.The car is running great, and actually the engine is running a little smoother. I read some of the previous threads on Check Engine probles. What is the stomp test, and haw do I perform it? I have a 93, 525i, 5 speed, 155,000 miles. Thanks

[HDhandyman]

Yesterday my check engine light came on for the first time. I recently filled up with Mobil Premium Unleaded. I always use Shell gas, but since I was getting low on fuel I didn't want to chance making it to my regular Shell station. The car took just over 16 gallons.The car is running great, and actually the engine is running a little smoother. I read some of the previous threads on Check Engine probles. What is the stomp test, and haw do I perform it? I have a 93, 525i, 5 speed, 155,000 miles. Thanks

It's probably my duty to respond to this. Check engine light is not from gas, especially if you used premium (which by the way, is not nessecary, you can use midgrade if you're here in the states). It's probably more likely the oxygen sensor or something like that. Have you changed it since you got the car? The O2 sensor asks to be changed via check engine light every 50,000 miles. If you are not the first owner, then 155,000 sounds just about right--assuming first owner didn't change it untill 55,000--make sense?

You can perform the check engine stomp test by placing the key in postion 2 (second position before cranking) and stomping on the pedal--all the way to the floor 5 times in 5 secs. If it doesn't work, then take the key out, put it back in to position 2 , and try again. There will be a slight delay--the light will hold once--then blip once--then display code. The code is a four number sequence. Take a pencil and paper, do the test, and then go here to check the results.

http://www.bmwe34.net/e34main/trouble/engine_codes.htm

Ciao,

Stephen