aapstealth

I have a 96 K1500 with the 4.3 Vortec automatic. Ever Since I got the truck the code Cylinder 4 misfire has been on. I have changed the Plugs, Wires, Cap Rotor, Spider Injector system with brand new unit including all components and gaskets. Fuel filter and pump. I have also tested the Compression in cylinder 4 and received a reading of 137psi. The truck does not seem to have a miss at all but is getting horrible gas mileage Driving like grandma going to the liquor store I might get 12-14mpg at best with NO AC mind you. If I clear the code it comes back in seconds and the only thing I notice is when the code pops up the idle drops about 50-100rpm. Also driving down the road the engine light sometimes goes off but will come right back on. Before replacing anything I brought the truck to a local GM shop that told me to ignore the light as the truck seemed to be running great. I dont mind the light but the MPG is killing me and IM thinking the light could be telling the ECU something false causing it to use more gas. Im wondering if anyone has had this problem or may know a solution

Mille Racer 69

well, I don't have that poblem but here are a few suggestions:
1-go to another shop, an independent shop will be cheaper and get another opinion.
2-for gas mileage get a tenneau cover or the bed to help with aerodynamics
3-also get a turbocharger installed to help with gas mileage. It atomizes the air going in so there is not an much unburned fuel giving you better efficiency.

But I would say fk the dealer if they won't address the problem and take it to an independent shop to have them fix it. call the better business beurou about shops you are interested in to find out if that shop has many complaints about them.

good luck!

aapstealth

When you say Turbocharger are you talking about one of those Vortex spacer things that sits in the air intake. Because if you mean a true Turbo Charger I dont think my wallet or Current engine could afford it

Mille Racer 69

yes, a true turbine that connects to the manifold

aapstealth

Unfortunately thats very far from my budget. Any other Ideas as to what might be causing the Light and Misfire?

Mille Racer 69

damn, sorry, not too much more of a mechanic,
good luck though