I have a 96 civic hatch with a d16y8 sohc vtec motor. I bought the car with the motor in it but it had the dx intake manifold, ecu and harness. I recently installed the correct intake manifold, harness and ecu and noticed the vtec did not engage. I then checked the knock sensor and noticed it was broken so I replaced it with a brand new one and plugged it in and still no vtec. I also tried it with my buddy's chipped p28 ecu and still no vtec. I would greatly appreciate anyone's input on this issue before I take it to a performance shop and get raped for probably something simple. Thanks

 

I'm guessing you have the DX head as well. Is her a VTEC solenoid on it?

 

Yeah..It has a Vtec solenoid

 

Is it wired for VTEC? Can you rev past 5500?

 

Yeah it redlines no problem but just no vtec. I even tried a tester on the solenoid and reved it past 5200rmp and nothing.

 

So how do you know VTEC is not engaging? It's not like a Nightrider turbo boost.

 

clean the vtec soleniod

 

I know it's not like a nightrider turbo boost...but I've owned several honda's and acura's and when Vtec kicks in you can hear it especially with an intake and I also put a tester on the solenoid and no voltage after 5200 rpm when it's supposed to light up. I also tried a chipped ecu from a gs-r and it lit up but it was misfiring like crazy.

 

low on oil????

 

nope it's good on oil

 

and the solenoid is clean..It's like i've tried everything and nothing works

 

vtec won't engage sitting still, so putting a tester on the solenoid won't work unless someone else was driving while you rode along under the hood..

if vtec isn't engaging, you'll have a CEL, which CEL do you have?

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/how-pull-cel-d4-srs-abs-codes-code-lists-1901557/

 

Oh ok..My check engine light is on but it's because the sensor that goes to the cat is not in...

 

are you sure thats your only cel?

 

I wouldn't get vtec to work while my cel was on.

 

that too.. handle with care haha

 

What rpm does it rev to?

https://honda-tech.com/forums/hybrid-engine-swaps-18/%5Bfaq%5D-%22my-vtec-doesnt-work%22-1812135/

 

Check ur vtec selenoid that is engaging right

 

it revs to about 7200 rpm.. I'm going to take the car to my local parts shop and use their diagnostics tool to see what cel codes I get and i'll post it tomorrow..

 

Perhaps the ECU is no good?

 

I tried a couple of ecu's..I have a p2p, I tried a p28, and a chipped p28..last week the vtec came on with the chipped p28 and after I put the new knock sensor, it never came back on with the chipped ecu

 

most chipped ecus will have the knock sensor deleted. you can get the codes on obd2 cars just like on obd1

 

ok I just hooked up the code reader and i got two codes..one for a evap and the other for a o2 sensor..I have the sensor that goes to the cat is not connected because I have a ex harness and theres no plug for the o2 sensor. I don't know what that evap code is about..

 

anyone??

 

the ex harness has the secondary o2 sensor in the cabin harness. u have to wire it urself with a shielded wire or run a dx harness and wire vtec its easier. this car must have been a dx from factory not an ex.