I recently put a ls/vtec in a 00 civic si, everything is fine except that we cannot get vtec to engaged or work properly. it is showing the CEL 6, 23. We are using a bi16 head, ls block b18a, and cannot figure out where the knock sensor is on a the ls block

 

did u did the install properly with the oil lines?

 

there is no place to put the KS on the LS block. you will have to fabracate (sp?) a place...see
http://www.c-speedracing.com/h...c.php

That is how I put my KS on my B18A block...

 

there is no know sensor on a ls block
most ppl use one of the alternator bracket mounting holes for the knock sensor

 

23 is a knock sensor and 6 is a temp sensor i think non of these codes have anythng to do with vtec engaging i went a whole with 23 being on i was using a gsr head and a b18a with a gsr ecu what ecu are you using and the only way i see vtec not working is because of oil pressure, you can check the oil pressure with a manual pressure gauge taped from the little test bolt next to the vtec solonide hope this helps you

 

vtec will not work w/o a knock sensor reading. it is a safety thing built into the ecu. on other option it to find a nut that threads onto the knock sensor and weld it to a bolt and thread the bolt to a hole in the block. that way you do not have to drill and tap anything.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by meanEG &raquo;</TD></TR><TR><TD CLASS="quote">vtec will not work w/o a knock sensor reading. it is a safety thing built into the ecu. on other option it to find a nut that threads onto the knock sensor and weld it to a bolt and thread the bolt to a hole in the block. that way you do not have to drill and tap anything.</TD></TR></TABLE>

That's why I have a chipped ecu. The programs out there usually do not the knock sensor so that higher compression could be achieved without sacrificing timing. That can be considered unsafe because of detonation, but it's all about getting enough fuel in there... My knock sensor plug is just hangin, don't need it with my setup...

 

You could eliminate the knock sensor problem completely by switching to a P28 ECU. Just a thought.

 

Thats not always true. We had a guy with a chipped p28 with no KS, and still had problems with vtec engaging. After the vtec solenoid screen was cleaned, it went away.

This may be the problem; even without the KS vtec will still engage, the engine does not go into limp mode.

If it is the actual temp sensor, check that to see if it has any debris that may be clogging it.

My guess is that there may be a loose wire thats plugged into the ecu on the harness itself. If the CEL comes on, pull over, check firmly with your hand that all of the wires are into their slots (letting the ecu lay flat on the floor may help where it puts less stress on the harness), and see what happens.

 

Vtec should still work eventhough the knock sensor in not plugged up. In order for the ecu to make the VTEC work it must have the water temp up to 160 degree F or higher, senses vehicle speed, senses load( map ), and you have VTEC oil pressure. last but not least have the VTEC activation wire hooked up correctly. also get your temp sensor cold fix if it is the coolant temp sensor.

 

If the engine is overheating, then its over the required vtec activation point....

but still, what ecu are u using?

 

i still say you are wrong about the knock sensor not being a required signal. it is just like the other needed signals. think about it. if you had bad gas right and the ign timing had to be retarded to compensate for it, why would the ecm want to engage vtec? it will not work

 

my jdm b16 swap has a stock p30 ecu and no knock sensor and vtec engages....CEL comes on and errything...

 

damn... its cool i guess

 

i am running a b18a block with a gsr head and gsr ecu and i get a code for knock sensor bur i can for sure tell you that vtec engages

 

Maybe it is for obd-2's, but for obd-1's it won't put the engine into limp mode with CEL.

Some people use the alternator mount on the back of the block to put the knock sensor. Not sure how well that works out, but all it is is a microphone.

 

Fix your engine temp sensor and you will have VTEC.