1989 Acura Legend check engine light does not come on & no red or yellow lights on ECU?
Asked by Scrapdaddy Oct 17, 2015 at 09:04 PM about the 1989 Acura Legend
Question type: Maintenance & Repair
Cannot pass smog with no check engine light that comes on for 2 seconds then goes out. ECU is not displaying any lights; let alone blinking! Checked bulbs, fuses & connections. Is it the ECU gone bad? Possible water damage?
3 Answers
Most emission inspectors require WEEK after the CEL comes on ,,, even for a second. ECU probably OK .. I suspect an O2 sensor is going bad ... easy to change .. all you normally need is a spark plug wrench and a jack, ( O2 is normally at the rear of the converter)
Scrapdaddy answered 9 years ago
So no blinking red light on ECU to identify code; no light at all, instead of 2 blinks? O2 sensor; ok. Will give it a try thanks. Does ECU need re-programming if replaced?
Nope .. it shouldn't .. one thing is a little strange regarding the Flashing light as soon as you start .. The O2 circuit is on a time delay that allows the engine to get hot before the ECU begins looking for a signal. That alarm must be stored in the ECU and it should give you a specific origin ,,, find a friend with a scanner and perhaps the code will help find it
