VTEC engagement problems

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Honorary Honda Driver
For those of you that don't know, i have a B20/VTEC in my hatch. well, if i'm at about 25% throttle or less and VTEC engages, the car begins to misfire really bad until i give it more throttle. but if i'm about 30% throttle or higher, then it engages smoothly like it's supposed to. it has done it since i can remember. i've had a stock b16 ecu, chipped P28, and stock P28 running the car at different times and with each ecu it does the same thing. now with the vafc and 450 injectors it's still doing it. any ideas?? i haven't played much with the vafc yet to see if it's a fuel problem but some how it just seems like it's not a fuel problem. let me know if any of you guyz or girls, have any info or ideas.

MODS/ADMINS: if this is in the wrong forum please move


Senior Member
Instead of tuning the V-afc to add fuel, use a fuel pressure reg. and tune the V-afc to remove fuel.

(Or something to that effect. This was told to me by someone that tunes a ton of Hondas and he said that V-afcs are better at cutting down the fuel flow than adding it. I really don't know shit about tuning)

Call Modacar and ask for Casey. He tunes Hondas all day. 925-371-5888