i did a 99 H22 swap into a 94 prelude si. just wired vtec up, plugged in new ecu and injectors. evrything ready to go. now im throwing a cel 23 for knock sensor. i have been running a p14 for the last week with no knock sensor code or any other codes. ever since vtec was hooked up today, knock sensor is throwing a code. any ideas, is it a bad ecu? i checked all plugs and splices and they are good, what else could it be. i doubt its a knock sensor failure with only 60,000 miles. would adjusting timing help anything. thanks.

 

just FYI you really shouldn't run an ecu that was programed for 240 injectors on a motor that has 290cc if your using the obd2 and its even worse if your runing 345s on a p14

the p14 should look for the knock too

with the p13 does the knock code show up immediatly?

 

actually i was running the p14 with 24occ's, it was only temporary for a week till the p13 came. any way i just plugged in the p14 and let it warm and rev at 3000, no code. then plugged in P13 and within 10 seconds of reving at 3000, the code showed up again. thats telling me its not the sensor but mabe the ecu? or somehting else? timing, fuel? i dont know, need help tho

 

HELP!!! limp mode sucks!!!!

 

anyoneknow anything. has anyones ecu ever had to be replaced for this reason?

 

u should have bought my ecu J/K It can be the ecu but i dont think so it may be a bad knock sensor or KS wire. I also have a new KS for sale but u might ditch on me.

 

Hey. I used to drive my prelude around all the time - maybe about 7-8months on a p14 ecu. But i had 240cc injectors in my car. It didn't run bad at all......

anyway, get an s300, disable the knock sensor and you'll be fine.

 

haha 92lude. i actually sent you an offer i figured it wasnt enough for you. anyway i may need it again. i gotta diag this problem first tho.

 

a knock sensor will not put your car into limp mode. It will turn on a check engine code. and even pull out timeing.

make sure that is the only code you are throwing. I car will drive fine with out a knock (maybe no vtec).

Are you running the right injectors with the p13? This seems way off but maybe you are noting that bad? (I dont think so)

 

Is there any OBDII - OBDI **** you have to do? I'm just tyring to make a suggestion, i don't know much at all about swaps.

 

injectors are right, they are the olive green tips from a USDM prelude vtec. only wires i had to change was the knock sensor i had to swap clips. other than that i used all the old obd-1 parts. is using the H23 distributor bad? i used it cuz i found on this site that it is ok to use. only code 23 is shwing, it just repeats itself and nothing else is happening. the engine light is doing something because when i accelerate hard before the light comes on the car pulls, vtec hits etc. then as soon as the light comes on it hesitates and i didnt take it far enough to reach vtec but i dont it would open up.

 

My brother's car is doing the exact same thing, its a 1996 SI with a OBD1 H22 swap.. It has the 330 OBD1 injectors and a harness to convert from OBD2 to 1 at the ECU. We are running an OBD1 P13. We have replaced knock sensors and it still won't fix it.. I really don't have a clue and I'm pretty competent about this stuff..

 

corey, i know this is probably below you but did you guys make sure the ign timing is set right??

also...when i did that exact swap, by chance it worked out right...

obd1 knock sensors are different, and i accidentally broke the obd1 ks during the swap, so i put in the obd2 and it has never given me a problem....try that...

the only visual difference is the plug, if i remember right, obd1 sensors are 1 plug and obd2 ones are 2....something may lose the signal from the 1 plug in the obd2->1 translation, not sure...it depends on the way they wire the ks wires....there should be two in the obd2 car....

im assuming both of you used the obd2 engine harness and modified it to fit the obd1 ks?? bc an obd1 harness wont plug up to your car....or at least it didnt for me...

 

when the car throws a knock sensor code it pulls out timing. so thats why the car is slower because of it.

as for the knock sensor did you tighten it to specs. ( I dont know how because there is almost no way to get a torque wrench in there)

also is there any way you wired it wrong or its grounded by accident or the knock is broken.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">corey, i know this is probably below you but did you guys make sure the ign timing is set right??</TD></TR></TABLE> Its well within range

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">obd1 knock sensors are different, and i accidentally broke the obd1 ks during the swap, so i put in the obd2 and it has never given me a problem....try that
the only visual difference is the plug, if i remember right, obd1 sensors are 1 plug and obd2 ones are 2....something may lose the signal from the 1 plug in the obd2-&gt;1 translation, not sure...it depends on the way they wire the ks wires....there should be two in the obd2 car.... </TD></TR></TABLE> I'm pretty sure that isn't true, they just have different plugs, but both are 1 wire.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">im assuming both of you used the obd2 engine harness and modified it to fit the obd1 ks?? bc an obd1 harness wont plug up to your car....or at least it didnt for me...</TD></TR></TABLE> yes, we used the obd2 harness, but modified it to change the crank angle sensor to work with the OBD1 dizzy..

 

mine is a little different that coreys. i have the obd2 engine in the obd1 car. i am using the obd2 KS that was on the original engine. all i did was splice the different clip onto it. its only one wire so i cant mess that up. is there anything wrong with this? also as i said before the P14 was not throwing a code for KS, ony the P13 but both look for it. ????

 

i know my timing is off also.

 

why is your timing off.

 

change to an obd1 ks then.....i know my obd1 ks doesnt like my obd2 ecu when i go for inspection...

yeah corey you are right....that was too early this morning to be thinking straight.....the difference is a circle plug vs a square.....

if i was a betting man i would say that the obd2 sensor is more sensitive.....

anyways, this i know for a fact....in an obd2 car (my 96 si) an obd2--&gt;1 ecu adapter with the obd2 h23 engine harness and an obd2 ks i had no codes with an obd1 p13.....oh and corey i did the same thing...i ran the 4 tdc/ckp wires up to the dizzy on my harness too....i made a nice peice...used some extra 4pin plugs, some sheathing and electrical tape....looks as stock as ever

is yours as clean as mine....(i doubt it)....haha

anyways, back on topic....

but when i take the adapter out and put the obd2 computer in it throws random misfire codes so there is definitely a difference in the sensors....i cant really give an explanation for your p14 lacking the code...but i wouldnt worry about it since youre not running that computer anyways....just get an obd1 ks....

i think a good rule of thumb is to use a ks that is the same obd as the computer....