Check Engine Light on low fuel

Wildman · Post by **Wildman** » 14 Apr 2009, 02:49

My check engine light came on for about 60 miles. I happened to be low on fuel (the first time). I put some 92 octane in and soon the light went out. Anybody have any insight into this. Could it have been complaining because previously I had put some 89 octane and some fuel cleaner in? Now I'm afraid to use anything but 92.

Post by **matthew1** » 14 Apr 2009, 11:59

Only bad things happen when you drive low on fuel. Reason: impurities collect on the bottom of the gas tank. When the fuel level is low, these impurities get sucked into the fuel system, and partially removed at the fuel filter.

If they make it through the filter you can get small debris clogging injectors or water pushed through to the engine. Any number of codes can be set.

I would guess this happened to your Volvo, then the additives/detergents or sheer volume of clean fuel cleaned up the mess.

Post by **VCA** » 16 Apr 2009, 05:51

matthew1 wrote:I would guess this happened to your Volvo, then the additives/detergents or sheer volume of clean fuel cleaned up the mess.

I'm actually thinking evaporative emissions problems. When did the CEL turn on? Was the car in motion, or were you at a stop? 8th character of your VIN # please?

Post by **matthew1** » 16 Apr 2009, 11:59

Or loose gas cap.

Wildman · Post by **Wildman** » 21 Apr 2009, 16:42

8th char of my VIN reading left to right is d. The light came on when I was driving on the freeway with two passengers - that was the end of at least half tank. Still hasn't come on one tank later.

Post by **VCA** » 22 Apr 2009, 06:08

Wildman wrote:8th char of my VIN reading left to right is d. The light came on when I was driving on the freeway with two passengers - that was the end of at least half tank. Still hasn't come on one tank later.

OK, so here's what I've gleaned from your car: you have 1st gen North American emissions and no leak detection pump. Your problem might be one of losing vacuum in the emissions system. On cars without the pump, leak detection is done at hot idle (while waiting for a traffic light for example) or at steady throttle (other diagnostics, such as the evap canister diagnostic are also done at steady throttle). You'll have to have the codes read when the CEL is on to be sure...generic OBD codes will suffice, you don't need to take it to a dealer.