having problems with my vtec, and yes, i searched.

Hey gang. i searched and was unable to find anything that would relate to my situation, so here it goes…
i have a 90 b16 motor in my 91 integra gs. i have replaced the head gasket, timing belt, water pump, distributor (whole thing), thermostat, and more that i can’t think of off the top of my head. basically, the problem i’m running into is that my vtec is engaging, but it’s not. :hmm:
most of the usdm dohc vtec motors the vtec crossover point is 4400 rpm’s, then at around 5500-5800, the vtec gets “angry”. well, i am not having a problem with my vtec engaging at 4400, but at 5800, it is not getting angry. sorry for the lame explanation, but this is the best way to tell you. i have reached the angry point twice, both times in third gear (don’t know if that makes a difference), so i know it works, but it seems to most of the time just not work. here is what i have done to troubleshoot so far…i have completely bypassed the vtec oil pressure sensor wires, the vtec selenoid wire, and the knock sensor wires, meaning i tapped into the factory connection and ran a new wire into the ecu to see if my wiring was the problem, and it was not. I was getting a knock sensor code and a map sensor code (codes 23 and 5), but after the head gasket replacement (the most recent replacement, thermostat was done at the same time), i reset the ecu, and i have driven around with the ecu code light in sight and have not thrown any codes. I am soooooooo confused right now. i also put a direct 12 volts to my vtec selenoid and it clicked, indicating me that it works. So, i’m really confused and don’t know what the hell i have to do so i can get my angry vtec. if anyone can help me figure out my problem i’m running into, it would be greatly appreciated. hopefully there is someone out there who is smarter than i. the only thing i have left to try is maybe upgrading my ground wires, but i don’t know if that is an alltogether different thing. my grounds seem fine, but i’ll do what i need to do to try and get this done, thanks for all of your responses in advance. :cross:

umm…last time I check and I could be wrong. but stock b16 vtec IS 5800. stock 94 and up GSR vtec engages at 4400, then secondaries on the gsr manifold open at 5500 where as vtec will get louder. not to be a dick, but I don’t really think b16 vtec is anything explosive. it’s just there. to ensure safer high revving. it’s not going to significantly pull. so unless it doesn’t work at all. I don’t think you really have a problem with it. or maybe I just misunderstood what you typed. good luck

B16 cams dont hit hard. Also it doesnt hit at 4400 unless you got a vtec controller. What ecu are you running. Also did this just happen or its been like this since the swap? If your car goes past 6000 and still pulls than the vtec works. If it starts to die like no more power than in fact its not working. Try this simple test. pr3 if you have vtec is at 4800, rev limit at 8200. Take that bitch to 8g if it cuts off at 6000 vtec or dizzy is not working.

i agree with posjr, b16 vtec doesn’t get very awnry until 6k. also vtec isn’t supposed to hit hard, its supposed to be smooth transition.

my b17 starts to really get loud from 6k mainly due to my removed resonator and KN filter. and even then its a slight difference in sound not something too discerning.


VTEC is at about 5,700 on a B16.

Its at 4,400 on a GSR (B18C1). Secondaries kick in at about 5750.

It shouldnt get “angry” unless your talking about it simply sounding meaner the higher you rev. If you can hear an audible change in tone, youre good to go. Dont worry, the B16 isnt going to be terribly fast stock.

that’s actually what i’m talking about. my car pulls fine, and i’m not having any problems in the performance dept. when i say the car gets “angry”, i mean around 6k it’s supposed to go from pretty loud to REALLY loud like most of my previous gsr’s and my friend’s 99 si. but it’s not. this is the problem i’m running into. other than that, the car runs great. i don’t know if anyone might have any suggestions to that, and i thank all of you for your quick responses.

It al depends o the engine, somties it’s jst not that loud when it engages. As for VTEC engagement, It varries on B16’s. but 100% of the B16 swaps I have done which is about 8, all engage at 4900 on stock PR3’s and stock PW0’s

thats what i was going to say :up:
mine engages at 4900 with stock pr3 and 4400 with chipped pr3. (i have 2 hehe)

and my friends 99 Si also is loud as fuck with just a short ram intake, but i can still take him. also, sometimes my vtec engages different too. it depends on where i start in the powerband i guess(like a downshift/punching it from a roll at 4k ect…) and if i am at WOT or not…sometimes its loud and “pops” open and sometimes its subtle and not that noticeable.

Yeah VTEC varries a bit with load as well.

interesting, i never knew that. yeah, i have a pw0 ecu, it’s not chipped because im’ thinking of going obd1. my vtec crossover point is at 4400 now, but with a new obd conversion and a chipped ecu, anything’s possible, right?

well stock tachs can be off… you could just as well be at 4900 at crossover. the most i’ve heard of a stock tach being off is about 500rpm so its a stretch but its possible.
well good luck anyway

“ran a new wire into the ecu to see if my wiring was the problem, and it was not. I was getting a knock sensor code and a map sensor code (codes 23 and 5) … and i have driven around with the ecu code light in sight and have not thrown any codes. I am soooooooo confused right now.”

i just did the conversion and im in exactly the same position… its sooooooo annoying !! i just give up and drive around with the light on lol and the ecu throwing codes at me

you probably have some plugs flipped

not sure… but they probably got it under control within the last 4 years :up:

hey not to burst ur bubble, but if u got a knock sensor code ur motor will never engage vtec. Ur factory ecu works on ur knock sensor. if it threw the code resetting might not help. if u want to bypass ur knock sensor u need a upgraded fuel management like hondata. also check ur vtec solenoid it might be that as well, anyways good luck with ur motor hope my .02 helps

i believe 4400rpm vtec activation (7200rpm rev limit) is an auto ecu. if so, i hope the motor isn’t an automatic version also. that would mean single valvesprings and some weird ass aluminum like retainer, which is prone to failure when revved above the factory rev limit. in addition, if it is auto, those cams are the smallest in the vtec line up. hence why it might not be hittin’. i didn’t know 16’s pull hard b4 7K?

This Thread Is Almost 4 Years Old.

november 2004

[QUOTE=4sd4dr;1885917]This Thread Is Almost 4 Years Old.

november 2004[/QUOTE]