Well, if you read my previous thread, https://honda-tech.com/zerothread?id=251240, checking and changing the oil didnt help. Checked it last week, and changed today. Although changing the battery did work. So, can someone explain why does changing the battery help re-engage the vtec?

 

a new battery resetted your ecu...

 

ok, seems logical.....if the battery was weak though, why would the car be able to start and all?

 

maybe your old battery wasn't weak at all, did you try disconnecting your old one to reset the ecu?

 

consider that vtec engages when conditions are met, and the conditions are checked by electrical sensors...
replacing the battery could have reset whatever electrical component was stopping vtec engagement, like the oil pressure switch, and incidentally u changed the oil at the same time...
did u ever figure out what CEL it was?
get autozone to test the old battery and see if it was in fact dead/dying?
chances are greater that it was oil related, not battery related.
plus like i told u in the im, this happened to me and it ended up being a bad filter, which caused the oil pressure to be screwy.
u changed the filter when u changed the oil right?

aet

 

yep, changed the oil filter. I have changed oil in my previous two cars you know . As for the battery, I already gave it to them. Actually it was O'Reilly Auto parts