SjCiViCHB

Okay, I tried searching, couldn't find anything related except just throwing the code but not the same situation.

Well I'm throwing a knocksensor code 23 on my B18c1 in my civic dx. Its a little wierd, the code only comes on after doing some accelrating/cruising during the afternoon when the engine is all warm. If i turn the engine off, and turn it back on, the light goes away, but then eventually comes back on after a few minutes of driving. However the cel doesn't come on at all at night. I've checked to see if the knock sensor is loose, nope. Wiring loose? nope. The light first came on when i was driving in the afternoon, and went over this big *** bump on the freeway. stopped at gas station, turned car off. turned back on, and the light went away. The light didnt come back on till 3 days later while driving home after work in the afternoon. I stopped and check to see if anything was loose, couldnt find anything. There is no knocking/tapping noise from what i hear. Reseted the ecu, started the car and the light went away after turning the car back on, and would eventually come back on after a minute or two of driving. But driving at night, the cel doesnt come on at all. Sorry if my explanation is complicated. Its late, and im tired, does anyone have any suggestions on what else i can do to solve this problem w/o disabling the knocksensor? thats going to be my last resort, i just want to make sure the engine is running fine before i go and do that.

egsleepercivic

reset the ecu and see if it still comes back on, if it does, redo the knocksensor wiring. you had to add it for the swap so that is most likley the culprit

SjCiViCHB

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by egsleepercivic &raquo;</TD></TR><TR><TD CLASS="quote">reset the ecu and see if it still comes back on, if it does, redo the knocksensor wiring. you had to add it for the swap so that is most likley the culprit </TD></TR></TABLE>

i did, goes away, and comes back on. I dont think its the wiring since i've had the swap in for about 3 years w/ no problem at all with the sensor. But ill just have to check on that also.

IHateJDM

check your wiring, then check your plugs to see if you are leaning out. maybe your fuel filter or injector(s) are clogged...

SjCiViCHB

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IHateJDM &raquo;</TD></TR><TR><TD CLASS="quote">check your wiring, then check your plugs to see if you are leaning out. maybe your fuel filter or injector(s) are clogged...</TD></TR></TABLE>

wiring checked. everythings is connected. Fuel filter was changed about 3 months ago. how do i check the injectors? i dont have a helms anymore, bastards stole it along w/ the car.

SjCiViCHB

would hot weather cause the knock sensor to go off or the engine to knock? Wondering since it only happens in during the afternoons, since its summer time here. Maybe I should flush my coolant system? haven't done that for a while for the motor.

Bump.

IHateJDM

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SjCiViCHB &raquo;</TD></TR><TR><TD CLASS="quote">would hot weather cause the knock sensor to go off or the engine to knock? </TD></TR></TABLE>

it can, if that's the case then retard your dizzy a couple degrees, and you should be ok.

greenblurr93

what octane gas are you using?

saleensolution

if you cant find the answer with your wiring or the sensor you may wanna try a different route like running a chipped p28 where it doesnt require a knock sensor

Tatakai

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IHateJDM &raquo;</TD></TR><TR><TD CLASS="quote">check your wiring, then check your plugs to see if you are leaning out. maybe your fuel filter or injector(s) are clogged...</TD></TR></TABLE>

how do u check to see if ur leaning out? im experiencing a similar prob (GSR in an EG Si)

and just after my code started going off (after it hadn't for a good 2 months or so when i finally installed a wire for it) i went to the dyno, and the o2 was reading extremely lean in idle and about middle of my rpm's

heh, sorry, im not tryin to thread-jack but i hate throwin codes!

SjCiViCHB

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by greenblurr93 &raquo;</TD></TR><TR><TD CLASS="quote">what octane gas are you using?</TD></TR></TABLE>

highest octane at the pump. 91

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by saleensolution &raquo;</TD></TR><TR><TD CLASS="quote">if you cant find the answer with your wiring or the sensor you may wanna try a different route like running a chipped p28 where it doesnt require a knock sensor </TD></TR></TABLE>

Yeah I plan on doing that soon, its just that I want to double check if the sensor is just going crazy, or if it really is detecting knocking.

SjCiViCHB

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tatakai &raquo;</TD></TR><TR><TD CLASS="quote">how do u check to see if ur leaning out? im experiencing a similar prob (GSR in an EG Si)

and just after my code started going off (after it hadn't for a good 2 months or so when i finally installed a wire for it) i went to the dyno, and the o2 was reading extremely lean in idle and about middle of my rpm's

heh, sorry, im not tryin to thread-jack but i hate throwin codes!</TD></TR></TABLE>

sall good dood, I hope we can both find out whats going on.

IHateJDM

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tatakai &raquo;</TD></TR><TR><TD CLASS="quote">

how do u check to see if ur leaning out? im experiencing a similar prob (GSR in an EG Si)
</TD></TR></TABLE>

Plugs are white when running lean, and black when running rich.

Tatakai

im guessing lean..

i do have some stage 2 or 3 (they're custom made- im the 2nd owner so i dont know that much) cams, and haven't yet upgraded my fuel systems or gotten any kind of tuning. im workin on all that stuff this weekend

so what would make the check light come on if we're runnin lean.. is the ECU like "its runnin lean, but no knocking? can't be right. *lights up*"

IHateJDM

the o2 can throw a code for running too lean, as well as the knock sensor detecting detonation. Either can throw a cel.

SjCiViCHB

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IHateJDM &raquo;</TD></TR><TR><TD CLASS="quote">the o2 can throw a code for running too lean, as well as the knock sensor detecting detonation. Either can throw a cel. </TD></TR></TABLE>

what if im not throwing an 02 cel? just the 23. The o2 sensor is off a civic sohc motor though. Does it matter what engine the o2 sensor comes off of?

Also what can cause the engine to go lean? I'm pretty much all stock. How do i check if the fuel filter is clogged, or if the injectors are? The fuel filter is only a couple months old.

Also, does outside heat/temperture come to play? like i said earlier, its hot as hell now, and the light only trips during the afternoon when im driving thru the hot weather. It doesnt come on at all at night, but its still kinda warm, just not blazin like in the afternoon.

Bump. Thanks for everyones replies though.

SjCiViCHB

bump for help

SjCiViCHB

another bump for more ideas. Checkin spark plugs today.

flood

Since you went over a big *** bump when it happened it could be a short. You need to tell if its a short or actual knock.

Unplug the knock sensor and check for continuity between the ECM/PCM connector terminals and the body ground. Then check for an open in the KS wire. Im not familiar with the pin out ecm/pcm connector on that car though so I can't help you there.

I also think that there are different codes for a malfunciton in the circuit of the KS and an acutal 23 KS code (OBDII). But not sure. Good professional Scan tools rule.

If you can replace it with a known good sensor that would help too. Do all the plugs look the same across the board? How old is your fuel filter? If one plug is whiter than the others could be an injector problem.

Just some ideas

Oh and temperature and humidity will affect an engine. Check timing and make sure its set to stock. Could be a bad batch of fuel too, did you fill up at the same place as always? If its really detecting knock thats bad mmmkay?

flood

Knock can be caused by a hot spot in the combustion chamber, improper timing, too hot a spark plug, low octane fuel, too lean an air/fuel mixture, or engine overeating.

SjCiViCHB

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by flood &raquo;</TD></TR><TR><TD CLASS="quote">Knock can be caused by a hot spot in the combustion chamber, improper timing, too hot a spark plug, low octane fuel, too lean an air/fuel mixture, or engine overeating.</TD></TR></TABLE>

Thanks flood! I'm gonna have to look into the too lean idea thingy. Cause I remember when i went in for a smog test, i didnt pass because of High Nox, and they said I might be running too lean. I dunno how i could be though, since the motor is pretty much stock.