I have a friend of mine who owns a '99 Prelude (VTEC). We've been trying to advance the ignition timing but everything we do doesn't work. We have looked for any info on how to do it and found out that you have to jump the service connector to do it. We did that too and nothing happened. Anybody have any clues on how to do this?

 

you can't do it, OBDII cars won't allow you, if you want to advance or retard the timing, you have to get some kind of aftermarket ignition that allows you to adjust timing

 

are you referring to OBDII cars in general or only to the Preludes?

 

OBDII Hondas in general, some of the integra guys claim it can be done by jumping the service connector, but the ECU still changes it constantly

 

The only guy that I know that has advanced his ignition timing has a 94 (ODBI) integra. Also I asked my mechanic about advancing it, and he said leave it alone, its fine from the factory. I even further inquired adjusting it b/c of the high elevation (I live in CO) and he still said don't **** with it.