That's how CEL's work - if it is on, it means a code is being thrown (long story short.) Any code it gives you, investigate what it is. The scanner may or may not give you a brief description, or it may just show you the code and leave you to google it. Sometimes you have to use your imagination and knowledge of how a vehicle works, depending on what code it is. For example if you got P0171, it could be O2 sensors (faulty or failed), MAF (dirty, faulty or failed), vacuum leak, etc. so it helps to start with the easiest fix and work your way up, maybe using the OBD to check if the afflicted parts are getting proper voltage. But (for example) if you have P0325, it only means one thing, that particular knock sensor is shot - no if, ands, or buts about it
It sounds much more complicated than what it is, and some people can find code scanning unnecessarily daunting, so I always recommend searching on google as a first step; usually something like
"4Runner
Code:
"[/I] or [I]"[year] 4Runner [code]."[/I] A while back I was told to google things as a first step because "chances are there's been a ton people in your position, far dumber and less capable than you," and it's very rarely failed me
OBDs will show you all recent codes that have been logged in your ECU. Sometimes your vehicle will log codes without tripping the CEL (called "pending codes"), but for your sake that's not really relevant here. Whatever the scanner tells you, post it here and search it up[/QUOTE]
Thank you Devbot. That helps a great deal. When I buy a scanner, I'll talk about it some more. One rather queer thing, I just tested the battery. It had only 11.3 volts. I say odd because I replaced the alternator last month and it was putting out 13.2 volts at idle
I can't help but wonder if the low voltage was the cause of the engine shutting off while I was doing the engine flush . Certainly it is the cause of the engine not even trying to restart right now.
IF I had a low voltage do you think that that MIGHT have caused the check engine light to come on ? Maybe a sensor was not getting enough voltage to work ????
Right now the battery is being trickle charged overnight.