1995 K1500 TBI 350 Running Rich

[IndexOf0]

I have not actually done this in so long (30+ years) that I don't remember it well. It's listed in the service manual, but I'm too lazy to look it up.

The light flashes with the engine running. The amount of time the light stays "on" versus "off" tells you rich vs. lean. The speed of the flashing tells you open loop vs. closed loop. Slow flashing is one way, fast flashing is the other, and I don't remember which is which.

I have an update. I unplugged all of the sensors one by one and the only difference was unplugging the CTS while running. It wouldn’t flood out the engine that way. Could I have gotten two bad CTS’s in a row? Could the grounds be at fault?

 

[df2x4]

Could I have gotten two bad CTS’s in a row?

Definitely possible. What brand of sensors are you using?

 

[IndexOf0]

Definitely possible. What brand of sensors are you using?

Ac Delco, not that, that means much anymore.

 

[Schurkey]

Connect a scan tool, see what the computer is receiving from the coolant temp sensor.