Help me you internet wizzards!

[ri06667]

Ive had an issue with my truck for some time now that my shop has failed to figure out.

Truck is a 92 ranger with a stock 2.3, manual 2wd.
My tach works at about half signal (2500rpm = roughly 5000rpm) and my check engine light is on. My idle is very rough and feels almost on the virge of stalling at idle.

So far I have changed all 8 plugs and wires, my ect sensor and cleaned my maf and checked for exhaust leak.

According to my engine diagnostic my iat is normal, my idle is about 825rpm, my ect has no issues and reads roughly 85 degrees at idle.
It is throwing these two codes on the key on engine running test
224 - Continuous memory - Erratic idm imput to processor
998 - Engine is operating in FMEM (Failure Mode Effects Management) and cannot be diagnosed in KeyOnEngineRunning mode

Which basically tells me to find and fix the codes displayed while running tests in engine off mode...
Unfortunately it doesnt throw any codes at all with the engine off...


Any suggestions would be welcome, Ive officially stumped myself as well as the mechanics at my work.

 

[fastpakr]

Take the ignition module out and have it tested at your local chain auto parts store.