ok i have a b16a in my hatch and i put in 2 different tachs and they both say the same thing. my rev limiter kicked in at like 7200 rpm and vtec popped at 5000. i checked the ecu and its not chipped. at least i didnt see the chip. its obd0 and its a pw0 ecu why is it doing this can someone help?

 

i think thats stock for that ecu(relivance/fact check??). why would you wanna go any farther than 7.2k any ways? get vtec/rpm controll device and you should be good

 

if your vtec is popping, i think you have a serious problem...as sh!ft said, did you check the specs of your ecu?

 

Your Rev limit should be 8200. Is there a check engine light? If so, what codes is it giving out? Check the little LED on the computer and count the blinks and report back

 

+1 I think vtec should be crossing over at 5500 as well if im not mistakin, and redline at 8200. Check if its throwin codes and come back

 

[QUOTE=scooterbuilteh2;40123996]ok i have a b16a in my hatch and i put in 2 different tachs and they both say the same thing. my rev limiter kicked in at like 7200 rpm and vtec popped at 5000. i checked the ecu and its not chipped. at least i didnt see the chip. its obd0 and its a pw0 ecu why is it doing this can someone help?[/QUOT


if you chip it you will be better off cause you can tune it for the full potential out of it

 

If I'm not mistaken, non-chipped ECUs will vary the VTEC engagement RPM depending on load.

 

obd0 pw0 and pr3 ecus crossover vtec at 4400/4600 and when vtec crosses over revlimit is at 8200. if vtec is not working or you have a CEL it will drop rev limit to 7200.

also when i was b16 with a pw0 vtec crossover never varied.

 

sounds like you have an automatic ECU or your engine isn't warm

info found here: https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/7k-rev-limiter-w-b16-277947/

 

ok no check engine light. vtec does pop i will take the car out in a little bit and see where the rev limit is for sure and where vtec pops. my old tach said like 4400 and rev limit at 7600. but this tach now i have to check again for sure but vtec popped at 5000 and rev limit at about 7200 but im gonna check again and report.

 

ok i just read the post about 2 diff ecus now this was in first gear. im gonna go first and second and see what happens.

 

ok dcvt16 is right. i took it for a drive and in first gear vtec didnt pop and the rev limit was 7200 second gear vtec popped and i could shift at 8200. now why doesnt my vtec pop in first?

 

is the speed sensor working properly? is the car fully warmed up? and is the oil level full?

 

ya all thats good sometimes i can hear vtec pop if i role into it and then punch it at about 4 grand. but idk why

 

well if you tune it you will get the full performance of the motor

 

ya i kno that but how is tuning it goning to make vtec pop in first when it pops in all the rest of gears accept first. i dont get it. we tune and we can make vtec pop at diff rpms and turn it off but not make it pop in one gear and not another. so idk