well ok i have a 99 civic ex with the basic mods I/H/E. I also have a si ecu and a vtec controller. For some reason i keep have my check engine light come on. when i had it checked they said it was the air fuel mixture. does any know how i can fix it. I have my Vtec engaging at 5000 rpms. I want to go to b16 injectors to get more fuel but not sure if i should or can do that.

 

Have you by chance put the car on the dyno to check the a/f ratio in real time? Also what vtec controller are you using and what are your settings? All this could help determine exactly what your problem is.

 

If you have stock cams changing your vtec setting can be hurting you, if you're not using a Dyno to tune it. Change it back to stock, get a cam cam gear, fuel pressure regulator, and tune it. Tuning works wonders...

And when you say Si ECU are you talking about the 99-00 SI ecu? I have never heard of any one using a DOHC ECU with a SOHC motor..

 

B16 injectors=240cc
d16 injectors=240cc dont waist your money

The check lights probles is because there is a voltage problem
Did you solder the cables of the controller to the ecu harnes?
If not do it

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GreenEX &raquo;</TD></TR><TR><TD CLASS="quote">well ok i have a 99 civic ex with the basic mods I/H/E. I also have a si ecu and a vtec controller. For some reason i keep have my check engine light come on. when i had it checked they said it was the air fuel mixture. does any know how i can fix it. I have my Vtec engaging at 5000 rpms. I want to go to b16 injectors to get more fuel but not sure if i should or can do that.</TD></TR></TABLE>

Common sense tells me to look at the vtec controller as the probable cause.
Was everything fine before the install of the vtec controller?
If so there is your answer.
You really need to have your car on a dyno ANYTIME you make adjustments to the air/fuel ratio and the vtec crossover. It's really pointless to make changes blindly (which without a dyno and wide band o2 is what your doing).
Speaking from experience, changing the vtec crossover needs to be done on a dyno. I installed my vtec controller and set it to 5,200rpm as a default before i got to a dyno, well there was a dip in the power band causing me to lose 20whp at the crossover, After a little adjustment we got that dip down ato about 3whp loss.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CivicSi2000 &raquo;</TD></TR><TR><TD CLASS="quote">If you have stock cams changing your vtec setting can be hurting you, if you're not using a Dyno to tune it. Change it back to stock, get a cam cam gear, fuel pressure regulator, and tune it. Tuning works wonders...

And when you say Si ECU are you talking about the 99-00 SI ecu? I have never heard of any one using a DOHC ECU with a SOHC motor..</TD></TR></TABLE>

Yes its a 99 00 si ecu my freind used to use one also.

Ok so if vtec controllers are so bad then y do so many people get them? I have the apexi Vtec controller

 

I have almost the exact same setup only vafc-2, and havent had any check engine light come on yet, and i got mine lowered to 5k also (thats without dyno tunning). i say check your ecu, cause that ecu isnt supposed to be on that engine and maybe thats setting something off.

 

i had it set to 46 the first time it came on then i changed it to 50 no prob for a while then last night i let a friend borrow my car and it came on while he had it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by props_honda85 &raquo;</TD></TR><TR><TD CLASS="quote">I have almost the exact same setup only vafc-2, and havent had any check engine light come on yet, and i got mine lowered to 5k also (thats without dyno tunning). i say check your ecu, cause that ecu isnt supposed to be on that engine and maybe thats setting something off.</TD></TR></TABLE>

Like i said my friend had a si ecu and vtec controller also. He had no probs i was wondering if it was the way i have the vtec controller setup. I wish someone could come and set it for me.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GreenEX &raquo;</TD></TR><TR><TD CLASS="quote">
Ok so if vtec controllers are so bad then y do so many people get them? </TD></TR></TABLE>

They arn't bad, they can be if used incorrectly or if you tune using an *** dyno.
They are a great tuning aid when used correctly, just slapping one one picking a few random number and going isn't using it correctly.

 

Thanks for helping me out I might be getting it to a dyno soon.

 

I live in Jax too, wheres the nearest dyno??