Reverse VTEC?

[OBD0SiR]

I have had a few civics with B16s now, but i have never encountered a problem like this...vtec sounds like it is engaging at 4600ish, but when it gets loud the engine seems to pull back. Its almost like when it engages, it loses all the power. It is a JDM B16a OBD0 with a pr3 ECU. i am also a bit confused about why vtec enages so low. thanks in advance

 

[4U2H8ME]

Dude, vtec on most models kick in @ 4500 rpm stock, unless chipped, or if you have a vtec controller. Now as far as power loss, you need to look into that. Sound like you have some sort of restriction going on.

 

[OBD0SiR]

this is my 3rd B16 and the first to engage at 4500...that is not the real problem anyway. i am most concerned about losing power. thanks for your input tho

 

[B16RacerN2NR]

No check engine lights? VTEC on a stock pr3 should be at 4900...

 

[OBD0SiR]

i thought it should be at around 5k...it is throwin a tps sensor CEL. VTEC wasnt engaging before and i figured tht was y, but i fixed some wiring issues ad it started screamin at around 4.5k. i had always heard that tps codes will make it not work. i was goin to hook up a light and see if it is engaging or what im hearing

 

[TurboMirage]

if you have a TPS CEL fix your TPS.

 

[OBD0SiR]

i bought a new one and installed it and it is still throwing the code. I reset the ecu about 6 times and i have tried switching the wires going to the sensor...didnt work, so i switched them back

 

[B16RacerN2NR]

did you make sure you adjusted it properly and it's reading .5 volts closed and 4.5 volts at wide open throttle?

 

[OBD0SiR]

thats what i was not too sure about...i have a morderate knowledge of cars and engines, but how do you adjust a tps?

 

[goldgreen90ef]

loosen both bolts/headless screws. backprobe with your dvom on the outer 2 wires.. move it around till at closed throtttle its at .5v and at wot 4.5-5 v. theres a ton of write ups, just google it. and yes you car will bog like shit when the tps is cooked.. i sucked water up my ebay long ram intake on my obd0 b16a...

 

[OBD0SiR]

thanks...i will attempt that tomorrow as soon as i get up. let you know how it turns out

 

[Justin66]

Make sure your vtec screen and air filter are clean also. Mine engages at 4400 RPM and one chip for 5800RPM. I think i should have it engage at 5000, but im not a dyno, im going how much "pull" i feel, i go nowhere til at least 5k.

 

[OBD0SiR]

i originally though it may be the vtec screen so i checked it and it was spotless...the air filter is brand new and still clean (obviously)...as far as the voltage goes, itwas reading .01V at idle and 2.67V WOT...it was turned all te way to the passenger side, upon turning it completely to the other side, it never reached even .15V at idle. does this mean the TPS is bad and I need a newone, or would it be a problem with the wiring? I am thinking that maybe the ecu is chipped because it seems to engage vtec at 4400 rpms and still engages with the CEL defective TPS

 

[K2e2vin]

Are you even getting a 5v reference voltage?

 

[awptickes]

The TPS should read 0.49V at closed throttle.

Ensure you're getting between 4.75 and 5.25V of power to the TPS.

 

[OBD0SiR]

i a thoroughly confused now. So i checked the reference voltage and it reads 4.97V...but when i was checkin the output of the TPS it read 4.36 at idle and .79 WOT...i thought maybe i should switch the outside wires and got .01 at idle and 3.07 WOT...i dont understand at all...please help

 

[OBD0SiR]

just an add on...i hooked up a temp light to the vtec solenoid and it is engaging at 4400 except when i am on the interstate...if i only have the gas at a quarter throttle it wont engage till 5400...i dont know if this is some sorta chip or if it is the TPS