I've got a quasi work truck 2003 S10 4.3 stripper, I've put an intake on it and yanked the MAF screen while in the process.

I've done this for years on all of my other cars and never had a problem, but now sometimes under extended full throttle (flooring it for at least one or two gears), the SES light will flash and stay on for a few days.

I pulled the code and it said "lean condition, bank one" or something like that, but I know what pinging sounds like and I don't hear any when this happens.

Also, I mainly run 93 octane in the truck but every once in a while it will get a tank of 87.

Should I worry about the light, or do anything about it?

 

Have you done the TB blade mod? Descreening the MAF does lean it out a little because it doesnt read all the incoming air as well, which usually gives you a tad more power. Especially on the pig rich 4.3's. I've never seen one throw a lean code before though. Are you running the stock air box? It could be spiraling the air and hitting just one of the sensors more, making it think there is alot more air coming in.

 

I put the K&N panel filter in and did the free cold air mod (cutting the lower half of the airbox but leaving the side that is facing the exhaust manifolds to block the heat).