Subscribe to a magazine

Yj Wrangler

Back to article View Gallery
3 of 12
EFI's overall goal is to keep the engine running leaner or as near "stoichiometric" as possible at cruise speeds or under normal loads - this is 14.7:1 air/fuel for the optimal burn of gasoline. Accelerating or heavy engine loading requires a richer mixture, which the system can also create as needed. The 4.0L engine delivers 20 mpg at highway cruise, retrofitted into an '87 YJ Wrangler chassis to improve off-road efficiency. Transmission is a freshly rebuilt AX-15 with overdrive, adding to good highway mileage.