97Camaro007

I was trying to replace the KS today because it wasn't reading any resistance......so i was going to replace......well it ended up rounding the KS and was just going to try to get a pair of vise grips on it and get it off......no luck.....it just broke off the top of the sensor so now the base that screws into the block is left.....i tried getting a chissle and try to chip it around but since the sensor is made out of aluminum it just chissle's off parts of the screw......well what i'm asking is i know it's been bad for a while now and it drives just fine......i was wondering if it is bad to drive it like this.....What is being done since it has nothing to determine Knock......is there another way to trick the computer into thinking that it's there.....The new knock sensor read 99.4 ohms of resistance and the one that is in the car read nothing because it was bad.......i have the LT4 KM also......Maybe a big resistor that read the same as the Knock Sensor.....Any help will be great!

Michael

CANTONRACER

Years ago when I first started toying with my Z28, my KS was unplugged when I bought it. Took it to the track, ran ok. Started looking into how to get more out of it and I eventually learned about the KS. Plugged it in, got all excited....not one bit of difference.

Some say you will get upwards of 12 deg of timing pulled if it is not plugged in...I scanned my Z with and without...no difference.

I even did the resistor mod...never made an ounce of difference.

I would just replace the thing and put the LT4 KM in.

97Camaro007

hmm......well i'm going to try tricking the computer into thinking that its still plugged up....by putting a 100k resistor in it and see what happens.....I can't get the other plug out until i pull the motor again so i'm trying to figure out a way to make it around it.........So i'm just going to put the 100 k resistor in it and see what happens.....anyone ever tried this?

CANTONRACER

Did you check to see if it was taken out or at least reduced tuning wise by pcmforless?

97Camaro007

not sure.....would a tech 2 be able to tell me this?

97Camaro007

I'm sure it's not taken out because he sold me a LT4KM with the tuning....i mean i don't think that he would send me that if it wasn't even going to make a difference....

z28coprice

another option is to just parallel them, if you have 2 sensors(but i think camaros only have 1 am i right or wrong). I have a '97 z28 LT1 in my b-body, my pcm is bridge soldered(meaning both knock sensors are connected inside the pcm) so that i only need to run the one(no performance gain or anything, just something i had BH do when getting programming). You could always take off the connector for the bad one, and just splice it with the good one. Should make it happy if you absolutely can't take it anymore.

97Camaro007

I only have one....that i can't get out and the top of the sensor is torn off.......i have to just find a fix until i can pull the motor later on....

shoebox

F-bodies only have one knock sensor.

Why bother with a resistor if you have a new sensor? Just plug it in and secure it. I am also guessing you meant it read 99.4k ohms?

97Camaro007

Yeah i guess that would work.......just make sure that its not rattling against anything.....right?

Injuneer

The PCM will definitely default to a knock retard "program" when the sensor is missing. I don't run a knock sensor, and I don't run the engine off the stock PCM, but the stock PCM is still "working" in parallel with the MoTeC ECU to provide the IAC control and the VSS output to the speedo. With the ScanMaster connected, it is showing DTC 43 for the missing sensor, and ALWAYS shows knock retard, varying from 1 - 12degrees. Even at idle there is 2 - 3deg of retard.

97Camaro007

doesn't the KS have to be grounded also though....i mean to make a complete circuit.....?

Injuneer

Yes... you have a single wire from the PCM to the sensor with +5V, and the other side of the sensor needs to be grounded to complete the circuit.

97Camaro007

Instead of using the sensor....i think that it would be a better install to just cut the wire where you would desensitize the km on the wire harness between the dipstick and ecu....and put a 100k resistor there and ground the other side......would that theorically work?