hi, randomly my engine management light has been coming on in the mornings, seems to be when the engine is cold, so I would assume it had something to do with the the automatic choke?
what happens : I go out in the a.m, start the car, its starts fine as per usual but faulters and the revs dont sit at 1 and a half like usuall, they rise and drop and sometimes will stall, but whatever the outcome of this the eml will come on. I've found from playing about that if I let the engine run (when poss) and it gets up to heat, I'll turn the engine off, then back on again and it will run properly as usual !
like I say though, it is random, sometimes it willl be freezing outside and I wont have any problems at all, I can just get in the car and drive to work fine.
what do you tink it could be?
cheers

 

Other HCF members have reported a similar issue where the Check Engine Light (CEL) turns ON while driving but, after an engine restart, it turns OFF. Based on these stories, it is my impression that, in certain circumstances, the CEL turns OFF if the fault does not recur when the engine is restarted. Nonetheless, the CEL code should still be stored in the car's computer, if you have not disconnected the battery or removed the 7.5A BACKUP fuse in the under-hood fuse/relay box. You should retrieve this CEL code(s) as it will likely tell you why the engine is experiencing occasional cold idle problems (for example a faulty or dirty IAC valve). These two websites describe the "jumper wire method" for retrieving CEL codes:

http://www.c-speedracing.com/faq/05.php
http://www.c-speedracing.com/faq/06.php

 

that brings me to my next question...... how exactly do I read the fault codes, I know you can buy a fault code reader or something but how do you use it, where do you plug it in or attach it?
Thanks
Denis

 

What year and model Civic do you have?

Some auto parts stores will retrieve the CEL code(s) for you free of charge (e.g., AutoZone). Alternatively, you can purchase a scan tool and do it yourself or use the jumper wire method explained in the websites in my previous post.

 

with my 89 Si every time it has come on it was because of a dead O2 sensor.