87 K5 running lean?

[87BrnRsd]

I have a 1987 K5 with a rebuilt 350, and tbi. Pretty much everything on the engine is stock. The truck is running pretty lean and I am wondering how to fix this. Sorry I havent given any more info, but I will pull the codes tomorrow to see if you guys can diagnose them. Thanks.
-Harrison

 

[84_Chevy_K10]

What makes you think it is running lean?

 

[K5MONSTERCHEV]

vaccuum leak?

 

[87BrnRsd]

Unburned gas in the tip of the exhaust pipe.
-Harrison

 

[js4x4]

unburned..?? I get H2O form/drip from my exhaust when shes tuned right...i'd think if you had unburned gas (rich?) and if ya have THAT much am surprised it runs...

 

[87BrnRsd]

Its not THAT much. It doesnt drip. If you put your finger in the tip of the exhaust and pull it out, its moist and smells like gas. Its throwing a code, so I am getting ready to go check it now. Will let you know what it says.
-Harrison

 

[dheavychevy38]

the base gasket on for the tbi is common for leaking check for the o'2 sensor also

 

[bablazer73]

I just went through something similar with the wifes truck. Was running lean, but the computer would dump fuel to try and comensate for it. The vacuum ports for the MAP sensor and PCV were plugged with carbon. the MAP wasn't getting a true reading. Cleaned them out and runs great now.

 

[87BrnRsd]

Thanks! I did that and it runs good now. Problem fixed.
-Harrison

 

[opfor2]

Where is the MAP sensor on a 90 Blazer ?

 

[bablazer73]

Right side of intake manifold, It's attached to a bracket thats just to the side of the Throttle body.

 

[opfor2]

Thanks, I'll have to clean it..

Dan...