Resetting fault codes without resetting ECU?

[pupp]

Anyone know if it's possible to 'cancel' fault codes without fully resetting the ECU by disconnecting etc. Reason I ask is I've reset mine twice recently... first time because I thought it was a 'good idea' after decatting etc, and second time after getting a MIL light and error code 88 that seems to be nothing too worrying. After both resets the thing has run differently... hanging onto revs for ages when coming to standstill, and just feeling 'off'. I think this is just adaptive settings being lost that will be reacquired over time but it's annoying. So, just wondered if the code cache could be erased by some other method than interrupting battery connection?

[GreenV8S]

I've never used one of these fault code readers myself, but from the way people have talked about them, I get the impression that they generally show one fault code at a time and you can clear the fault code to show the next one. However, if everything is working correctly then I wouldn't expect resetting the who ECU to have a dramatic effect on the running of the engine. Is it possible there's some significant fault which is making it run very poorly until it eventually drops into 'limp' mode? I'd have expected to find evidence in the form of fault codes if this was happening.

[pupp]

Multiple codes do show apparently (I forgot to check before resetting doh!), but are accessed by a process of stopping and restarting the motor and by disconnecting/reconnecting the reader (I may have the sequence wrong), which brings up the codes serially...don't think the 'read' codes are cleared off however.

It's not a case of the car running 'badly', it just behaves differently to what I'm used to and I don't like it...