Surging idle after leaving for a few days

[Norv]

Hi all,

I've been away for 10 days and not had the civic long. The battery isn't the strongest, I have a new one to fit but haven't got round to it yet. The car started up better than I thought it would on my return. I left it running for a couple of mins to charge back up a bit and it started surging.

Fired it up it ran to 2k for a while, then dropped to about 1600 ish quite suddenly. After another minuteborb2 it then started pulsing from 1500 to 2k back and forward for a minute or 2. I then took it for a drive and let it warm up properly then gave it full throttle a few times.

After the drive it was at normal idle speed and all seemed fine. Is this a learning process for it? Are they funny about battery voltage flickering a bit low while trying to start it? Or is it likely a dirty throttle flap or a dodgy reading from the position sensor? It's always started and driven lovely for the month I've had it before this happened.

Cheers, Mark.

 

[Hazz]

Idle air control valve.

Common issue when left for a while or driven for long periods without hitting vtec. Usually a full throttle blast will clear its throat but if it's particularly dirty then you may need to take it apart and clean it. There are guides knocking about on t'interweb on how to do so. Fairly easy job, takes a couple hours if you've never done it before.

 

[Norv]

Ah that's cool, cheers hazz. Similar happened to the golf 1.8t, I'm a mechanic so should be easy enough. Spent ages cleaning the golf one up, makes a big difference. I'll add that to my list of jobs! Thanks mate.