I just purchsed a 1.5l, 93 Civic Hatchback and I notice that when I start the car initially (in the morning or after work) ater a long period of not running, the cars revs for too long. Normally the car should rev high for a few seconds and then stabalise but it takes a good 2 minutes (not idling but driving) before the car comes down to normal.

I don't know what kind of maintenance the old owner did on the car so I'm wondering if this is just a case of improper maintenance and the car needs a tuning, or is this something bigger like a sensor issue.

Please help.

 

Is the CEL ON?

I would recommend that you remove and clean the IACV and Fast Idle Valve.

 

This i my first civic and I've only had it a week so I'm still not too failiar with the engine and components so how exactly would I check if the CEL is on?

 

If the yellow engine symbol in the gauge assembly stays lit or occasionally lights when the engine is running, then do this:

http://www.honda-tech.com/zerothread/1901557

 

Sorry, don't think I'm slow, I just didn't realise that CEL meant Check Engine Light. I thought it was some kind of fancy civic sensor or something (since most have acronyms). In this case, no, the CEL is not on and doesn't come on occasionally either.

 

Sorry for the overuse of acronyms.

Try cleaning the Electronic Air Control Valve (EACV/IACV) and the Fast Idle Valve. Both sensors are located on the throttle body:

 

I'm not necessarily convinced that this is a problem. If the car hasn't been used in a while and it revs at a high rpm for a couple minutes, that's not unusual. It certainly does this in my car when it's cold outside and it needs to warm up.

 

Mundy, you could be right, depending on how high the rpms are when the engine is warming.

 

How high is the rpm at?

If very high, like Ron said, you need to clean your throttle body, could be buildup of carbon in there