Thread: Bad Knock Sensor = Retarded Timing?

I was helping a friend with his car, he has a 94 G20 that he put a lowport into. The car runs great, and drives fine but he thought it felt sluggish. So we started looking at some things and found that when he accelerates the timing is being pulled back down to 15-17*, but when just cruising it will come back up to where it should be at that RPM, 30-40* range.

I am thinking it is the knock sensor but i am not sure what else will pull timing like that. The car is stock except for an intake, base 15* timing, plugs & wires are fairly new. It idles right at 850RPM when warm.

What else should we check? I am going to make a fake knock sensor to test this theory but i wanted some input as well.

sounds like a knock sensor.

does the ECU shows the knock sensor code?

Yes, The car was started 8 times since the code was there. I reset the ECU and it did not through the code during our test drive but was still pulling timing back.

Do you have a spair one ?? I might have on in my tool box , are they the same from b13/b14 , and JDM det ect ??

My b14 did the same thing when I swapped in the ve. I used the knock sensor that came with the engine and it would pull the timing @ around 4-5k rpm, but other than that it ran fine. I swapped the knock sensor from the de and never had this problem again and the cel hasn't thrown this code anymore. Now the only code I have is for the lightweight flywheel (F1)

Happened to me. It pulled timing at peak torque for me, around 5300 RPM. Pulled the timing all the way down to zero. Car would jerk harshly and shutter at that RPM.

that graph wasbwhen my knock was useless
as u can see, i was wot and timming on 7°

suppously my timming was set 18.6°
was "cold" weather (18-20°c its like 70°f).

amm....
car was hitting on the drag strip 16.6 and slower.

gas consumption was horrible, it increased waaaaaaaay much.
hope it helps.

Ok, so i will have him swap it out. I have a known good one and a "i think its good" one as well. Thanks for the input.

Ruben,

That is exactly what his car is doing.

Also i forgot to tell, my check engine light wasnt on, and knock sensor thrown by the DS and said:
code 34: 0 times started