vtec not kicking in?

[mikey_t8]

so, not had my dc5 for long and already experiencing problems..

in the first few weeks of driving, when i'm going around 3-4k revs, the sound of the engine changes which is where i believe vtec starts to kick in...

but for the past couple of days, feels like she has been lacking abit of power, and today when i was going between 3-4k revs, the sound never changed, and stayed the same..


any help or advice would be appreciated

 

[ste01]

Vtec doesn't come in that low on a k20a

 

[dotty]

Checked the oil level ?

 

[DC5RS]

If stock ECU it should engage vtec at 6200rpm

 

[RE Spirit]

If stock ECU it should engage vtec at 6200rpm

^^ This

 

[mikey_t8]

Checked the oil level ?

yep.. oil is just under the max mark when cold, checked it when it was warm too and its just over the max line by about 5mm

 

[mikey_t8]

Vtec doesn't come in that low on a k20a

i been told it starts around 4k, hence the sound change or something.. but it doesn't fully kick until around 5-6k

 

[RE Spirit]

i been told it starts around 4k, hence the sound change or something.. but it doesn't fully kick until around 5-6k

VTEC engages at 6200rpm on stock ecu's.

Suggestion would be: warm up your engine and give it a try to give yourself a peace of mind

 

[DC5RS]

i been told it starts around 4k, hence the sound change or something.. but it doesn't fully kick until around 5-6k

Sorry i am noob with mechanics but at 4k it starts the second ( if i am not mistaken shaft or something) hence the sound change

at 6200 starts the vtec.

 

[Wingnuttzz]

Any chance it could have an aftermarket ecu, i.e K-Pro as it could have a variable vtec point.

 

[mikey_t8]

Any chance it could have an aftermarket ecu, i.e K-Pro as it could have a variable vtec point.

no idea which ecu it has.. i been told the car is all oem, with hondata air box mod

 

[wj51fut]

VTEC kicks in at 6k revs.

There is no second cam or lobe effect on these cars. Trust me, I've taken mine apart many a time.

VTEC won't kick in unless all the parameters are met ie; oil level, oil temperature, water temperature etc. you also need to fully depress the accelerator pedal. There is a certain degree on which the TPS sensor reads (think its 70%) then it engages VTEC. If you slowly rev up to the 6k it won't kick in. Hence the ivtec.

If the car hasn't been used a lot then the VTEC solenoid could be seized. DavePingu had this and is easily replaced.

Make sure the car is up to temperature
Make sure there is enough oil
Make sure you put your foot flat to the floor around the 6k crossover

Other thing to look for is the oil pressure switch sensor lead the goes just above the oil filter. This can easily be broken or dislodged during an oil change.

HTH

Adam

 

[mikey_t8]

VTEC kicks in at 6k revs.

There is no second cam or lobe effect on these cars. Trust me, I've taken mine apart many a time.

VTEC won't kick in unless all the parameters are met ie; oil level, oil temperature, water temperature etc. you also need to fully depress the accelerator pedal. There is a certain degree on which the TPS sensor reads (think its 70%) then it engages VTEC. If you slowly rev up to the 6k it won't kick in. Hence the ivtec.

If the car hasn't been used a lot then the VTEC solenoid could be seized. DavePingu had this and is easily replaced.

Make sure the car is up to temperature
Make sure there is enough oil
Make sure you put your foot flat to the floor around the 6k crossover

Other thing to look for is the oil pressure switch sensor lead the goes just above the oil filter. This can easily be broken or dislodged during an oil change.

HTH

Adam

thanks for the info..

i just got in from a little drive.. hit 8k revs, no vtec, no kick, no bwaaaaaaah.. engine was properly warmed up first.. drove around town for 5 mins before i went somewhere safe to floor it

have i done any damage by hitting 8k and have no vtec?

 

[davidpingu]

Does the Eml light come on at all? Even during start up sequence? If it comes on at start up but then goes out I'm surprised it isn't coming back on.

I vaguely remember reading that an O2 sensor can sometimes stop engagement without throwing the light. Not sure if anyone can confirm?

No you won't have done damage if there is oil in it and it was warm

 

[Brecht]

5mins around town isn't really going to be enough to get the oil up to the correct temperature would be my guess.
but hey , i don't even know what temperature is really needed to activate vtec
I usually drive for about 6 miles before i even go above 3.5 - 4k revs..
Did try going into vtec once when it was stone cold , just to try it because people said i couldn't.. but it did activate.. ( oem ecu ).
few members on here have had problems with the vtec solenoïd before if i remember correctly
first check all the things that have been said above before, if you don't have the knowledge for it i'm sure there will be members willing to help you out

 

[Linus27]

With just the Hondata air box mod, you won't get any bwaaaaaah, more of a rush feeling within the car. I have just come from an EP3 with AEM V2 and you could tell when VTEC kicked in purely from the noise. Now moving over to a DC5 with OEM airbox, VTEC is very subtle and a few times I had to double check it was working. The way I could tell is not even look at the revs and see if I could feel it and yes, every time I felt it, I checked the revs and they were on 6k. If your car is OEM, then VTEC will be very subtle.

 

[Brecht]

you can hear a ever so slight changeover from the engine even with the oem airbox , if you can't hear it you sure as hell will feel it though..

 

[mikey_t8]

Does the Eml light come on at all? Even during start up sequence? If it comes on at start up but then goes out I'm surprised it isn't coming back on.

I vaguely remember reading that an O2 sensor can sometimes stop engagement without throwing the light. Not sure if anyone can confirm?

No you won't have done damage if there is oil in it and it was warm

nope.. eml light hasn't come on... not sure about the start up sequence.. never really pay attention to it if im being honest..

5mins around town isn't really going to be enough to get the oil up to the correct temperature would be my guess.
but hey , i don't even know what temperature is really needed to activate vtec
I usually drive for about 6 miles before i even go above 3.5 - 4k revs..
Did try going into vtec once when it was stone cold , just to try it because people said i couldn't.. but it did activate.. ( oem ecu ).
few members on here have had problems with the vtec solenoïd before if i remember correctly
first check all the things that have been said above before, if you don't have the knowledge for it i'm sure there will be members willing to help you out

not really sure myself tbh but i always pay attention to the engine temp gauge and make sure its up at its regular position (40% up)...

im really a car noob who's starting to pick things up as i go along so i asked a honda specialist who dealt with a few dc5 on here about the problem and probably take it to him when i have my next day off...

With just the Hondata air box mod, you won't get any bwaaaaaah, more of a rush feeling within the car. I have just come from an EP3 with AEM V2 and you could tell when VTEC kicked in purely from the noise. Now moving over to a DC5 with OEM airbox, VTEC is very subtle and a few times I had to double check it was working. The way I could tell is not even look at the revs and see if I could feel it and yes, every time I felt it, I checked the revs and they were on 6k. If your car is OEM, then VTEC will be very subtle.

nah, i definitely can hear when vtec kicks in, and feel it... but can't feel or hear it at the moment.. when it does kick in, its loud loud, but it's still noticable

 

[Col R]

VTEC kicks in at 6k revs.

There is no second cam or lobe effect on these cars. Trust me, I've taken mine apart many a time.

VTEC won't kick in unless all the parameters are met ie; oil level, oil temperature, water temperature etc. you also need to fully depress the accelerator pedal. There is a certain degree on which the TPS sensor reads (think its 70%) then it engages VTEC. If you slowly rev up to the 6k it won't kick in. Hence the ivtec.

If the car hasn't been used a lot then the VTEC solenoid could be seized. DavePingu had this and is easily replaced.

Make sure the car is up to temperature
Make sure there is enough oil
Make sure you put your foot flat to the floor around the 6k crossover

Other thing to look for is the oil pressure switch sensor lead the goes just above the oil filter. This can easily be broken or dislodged during an oil change.

HTH

Adam

^This exactly

As Gok says, start by checking the sensor. If all's good there then its likely to be the vtec solonoid.

That's where I'd start anyway...

 

[Rom]

Guess no 'vtec vent' in these like my old EF8 then

Had a lever on right hand side, that opened a flap within the air vent ducting from the engine bay....Insane.