This well maintained car invariably started and ran well after complete engine overhaul 20K miles ago when master relay, O2 sensor & fuel filter were replaced with OEM parts. Engine unexpectedly refused to start one morning. Engine turns over properly and cylinders fire irregularly but never enough cylinders to start engine. Acts as if engine is fuel starved. Fuel pump heard to operate for two seconds after ignition turned on; check engine light goes out as soon as starter engaged; no codes set on ECU. Shop manual suggest checking ECU but I don't have the test harness or a known good ECU to substitute.

QUESTIONS:
1) Does anyone know how the cold start fuel enrichment cycle works on this car and how I could test for a problem there?
2) What additional tests should be performed to rule out ECU problem? Given age and low value of car buying a replacement ECU is uneconomic.
Dennis Waller
denniswaller@comcast.net

 

Thats a tough 1 but ecu's usually don't go out that easy.