So after checking pretty much everything else and still getting lousy gas mileage and having a strong gas smell at idle, i decided to disconnect the plug to my cold start injector (thinking it is always stuck open). Truck cranked a little longer than usual, but once started, ran fine in both open and closed loop. What was odd is that after getting off the highway, at idle, the Parking Brake, A/T Oil Temp, and the Battery Light came on. When I started moving again, the lights went out. At the next traffic light, they came back on. Anyone else experienced this and have any insight?

 

Charging system fault, when "L" signal of alternator goes low, will cause all three of the above lights to come on.


Grab a multi-meter and check your charging system according to this.

Best of luck.

 

Thanks for the help! I will take a look at it this weekend.

 

RAD4Runner is likely correct. As far as why the lights started coming on after you disconnected the CSI, it may simply be because the truck is now idling at a lower rpm and the alternator can't charge the battery at such a low speed. A good sign that your charging system needs attention.

 

That's exactly what I was thinking. The alternator looks pretty bad (noticed it before), but it never made any noise, so I left it alone.