Okay i got into this little "scuff" with this dude on another Web site.

the arguement is...".if your check engine light is on..(in this case for the knock sensor) the computer will run in "limp" mode." therefore not running the engine at its full potential

Just to make sure i am right......is this satement true or false....and could you say why?

 

wat is limp mode. ecu sends knock sensor and runs fine but turns off when it idles low. the idle goes all the way down. other than dat is runs great

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pelon 1990 civic si &raquo;</TD></TR><TR><TD CLASS="quote">wat is limp mode. ecu sends knock sensor and runs fine but turns off when it idles low. the idle goes all the way down. other than dat is runs great</TD></TR></TABLE>
maybe i missed somthing.....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Madspeed &raquo;</TD></TR><TR><TD CLASS="quote">Just to make sure i am right......is this satement true or false....and could you say why? </TD></TR></TABLE>Both. Or neither...

It depends on WHY the check-engine light is on.
What error code is it throwing? Some of them disable VTEC. Some of them set a lower rev-limit. Some of them do both. Or neither...

 

A CEL for a knock sensor will throw you into "limp mode". Your spark managment system knows the engine is knocking and it doesnt want it to be fatal. So it retards the timing so that it will not predetonate. All CELs dont put your car into limp mode. It's simply a safe mode so your car wont damage itself due to spark-knock.

 

so on my lsvtec i m runnin a pr3 ecu and i have no knock sencer..and the chip is in limp mode is this cuz i have no knock sen hooked up???...if i hook the knock sencer up will it run fine?????

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by snowbunny &raquo;</TD></TR><TR><TD CLASS="quote">so on my lsvtec i m runnin a pr3 ecu and i have no knock sencer..and the chip is in limp mode is this cuz i have no knock sen hooked up???...if i hook the knock sencer up will it run fine?????</TD></TR></TABLE>

yes

check this thread out

https://honda-tech.com/zerothread?id=1181854

 

I don't consider the check engine light being on and the ecu pulling a little timing to be limp mode, I call that safe mode. True limp mode is a *****, 3000 rpm rev limit, incredibly rich, lots of stumbling, etc. This usually only occurs with an internal failure of the ecu.

 

on my car i have no knock sen hooked up and i have a pr3 ecu and a spoon chip and the red light on the ecu stays on steady...and wont rev over 3500....but if i put another chip in thats got the knock sen disabled everythin is fine...i didnt no if it was a bad chip or cuz i didnt have the knock sen hooked up....but if i plug the factory chip in...it only thorws the knock sen code...and the red light dont stay on...wtf?????y is this???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drdisco69 &raquo;</TD></TR><TR><TD CLASS="quote">I don't consider the check engine light being on and the ecu pulling a little timing to be limp mode, I call that safe mode. True limp mode is a *****, 3000 rpm rev limit, incredibly rich, lots of stumbling, etc. This usually only occurs with an internal failure of the ecu.</TD></TR></TABLE>

or a bad coil will do it too

 

thanks for all the responses.....I feel smarter now.

 

my check engine also came up tonight while i was driving for no apparent reason, i tried lookin around but didn't notice anything wrong . can anyone help me?

 

jump the code