Notes On Intermittents

Check for throttle shaft and throttle blades binding, weak or distorted throttle spring, cruise or TV cable binding, and/or properly installed TPS.

Intermittent code "EO27" can be induced by resting foot on accelerator during key on/key off for 10 seconds cycle. Check for intermittent open on circuit No. 427 between ECM and ISC.

Fig 1: Hard Trouble Code E027 - Open Throttle Switch Circuit

Fig 2: Hard Trouble Code E027 - Open Throttle Switch Circuit

Fig 3: Schematic for Hard Trouble Code E027