Question about running Lean?

[smokey668_99]

I was driving home yesterday down Rt. 80 in New Jersey and my check engine light came on. So I have the Logger program for the laptop and I hooked that up and the code said that the system was running to lean. Does anyone know what would cause that? The only thing I did that day was drive around and I raced two cars. Both times I went to 110 and then slowed down. But it wasn't until after I slowed down and just cruised that it came on. Any input as to why this happened would be great.

Oh yeah the light went away and never came back after I cleared it.

[Blk00SS]

Lean = Not good.
Means the car isn't getting enough fuel.

How many miles you have on the car? Run some Fuel injector cleaner if you have alot

[smokey668_99]

That's what I figured. The car has 39000 miles on it and I have never had this problem. But even after the light came on the car still ran fine. It didn't seem different at all that's why I didn't think much of it. But I'll try the Fuel Injector cleaner just to be safe and hopefully it won't happen again.

One other thought I had was that I know some people get a CE light when there gas cap isn't on tight. Could this have caused it? Just a stupid thought!

[SlasherX]

Originally posted by smokey668_99
That's what I figured. The car has 39000 miles on it and I have never had this problem. But even after the light came on the car still ran fine. It didn't seem different at all that's why I didn't think much of it. But I'll try the Fuel Injector cleaner just to be safe and hopefully it won't happen again.

One other thought I had was that I know some people get a CE light when there gas cap isn't on tight. Could this have caused it? Just a stupid thought!

gas cap? no...i highly doubt toyota has some exact bar vacuum needed for your gas tank to that degree..haha..

run injector cleaner, make sure your plugs are ok..thats the first way to tell whats going on, and also help you know which cylinder it is. if the problem still persists, take it into toyota..you also may be running bad gas..it happens..what octane you running, are you running above 91 like you should, or what?

also..in an n/a car, lean conditions can occur from time to time. keep watch on injectors, CE's, and plugs...run that injector cleaner.

[smokey668_99]

Yeah the gas cap. I thought I saw someone on here post about that. When you get gas if the guy doesn't tighten it all the way the CE light comes on. I know that it happens in some Ecplipse's. But I will go today and buy the Fuel Injector Cleaner. Is there a certain brand or anything? As far as everything else it all checks out OK. I mean I ran the logger yesterday and graped out both O2 Sensors and they are both fine and I checked everything else that I could and it was all at normal levels. And I always use Super in it. Nothing else ever has gone into the tank.

Thanks for the input guys.

[gumber]

In regards to the gas cap. If a gas cap is over tightened and for some reasons the valves inside it won't open, what happens is you create a vacume as you consume gas. Eventually it becomes too hard for the fuel pump to suck gas on most cars and basically you run lean or at the worst stall out. If this is a case simply unscrewing the gas cap (you'll feel the presure and should hear a whoosh) will fix it. If it happens again your gas cap should be replaced.