Unplug your Knock sensor and find some lost power

Found this mod on TeamZX2(which is down at this time :frowning: ). By unplugging your knock sensor you will get a smooth power band with much more pulling power. It is just above your oil filter to the left and has a green plug on it. The release tab is on the bottom of the plug. Just press up on it while pulling the wire. I have done this and no longer have the power surge above 3000 rpm. It has the power from start all the way to max RPM. You might have to run 89 octane fuel, I did. YOU WILL NOT GET A CEL LIGHT.

My car is much more fun to drive :smiley:

I’m also here from the teamZX2 site & recently disconnected the knock sensor.

The tab on my '02 was on the top & popped off easily after I figured that out.

The power increase is noticeable & may be giving a little better mpg around town. I run BP regular & notice slight pinging only when lightly accelerating uphill in 5th. I don’t want to use 10% gasohol because that consistently costs me 3 mpg less mileage. I have kept all my gas receipts & milage data since I bought the car 4 years ago (36,000 miles).

What is that sensor used for anyway?

To detect any type of ‘knocking’ in the engine. Its supposed to indicate if there might be a problem developing with your internals.

No cel, but will it pass the computer check for inspection?

THAT keeps the engine from revin up as strong as it can go? Hun. Well if I don’t HAVE to use premium, then I think its a good mod after all. Can’t afford premium right now anyways.

In effect the knock sensor is like a back up for the computer to make sure that its not over advancing the timeing. If for whatever reason (obviously the timing curves of these cars isnt too extreme lol) it senses a lot of detonation it will start to retard timing by a degree at a time across the entire power band untill it sees it go away. Thats One of the reasons they run much better when its cool outside or the engine is cooler, the hotter the combustion chamber the higher the likelyhood of pre-ignition.

A/C noise can also activate the knock sensor. Or any other noises attached to the engine.

I’ve switched to 89 BP fuel. Getting batter fuel millage.

Shouldn’t have any effect on this. It is used to detect ping noises in the engine and retard the timming. But it also picks up all the other engine noises too.

Yeah, luckily for us the EEKV cpu in our cars isnt as advanced as most of them, or it would detect a ckt fault and set a mil lol in theory it should allow the engine to run the full programmed timing curve, I would strongly recommend not unpluggin it if your in higher altitudes or run regular, detonation can severly damage the piston surfaces and rings.

Well, if the SCT can achieve the same effect, yet the sensor is still active, then I’ll keep it plugged in.

the correct way to do this it to wrap the threads of the knock sensor with teflon tap there for making it less sensitive to internal vibrations but still allowing it to work on such errors as preignition and detenation. and it is emissions legal.

Sounds like the best solution to me besides just leaving it alone.

I said it on Team, and I’ll say it here. I tried this within the 2nd week that this “mod” was out. I got rattle sounds and clicking out the ass around 2,250 and 2,600 rpm from my engine. Yea, the power curve was smoother, and it pulled a lil more up higher, but I like my engine, and I want to keep it operating correctly so I plugged it back in.

I even ran down till the needle was on the red line for gas and filled up with 92octane, same result…

Did you still have your VCT?

I don’t have a SR. But I run 89 and I have no ping unless I’m in 5th and going up a steep grade. My PCM is a LXQ2.

This actually made my car drive a lot smoother. When I would shift it was enough to cause the knock sensor to go off and retard my timing, and drop my RPM a little bit and cause it to stutter slightly when I first was in gear. That has completely gone away and general acceleration is also MUCH smoother.

:mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen:

It seems people w/o S/R PCMs the “mod” works fine. I have talked to a few other S/R owners through AIM and they have had the same problem, they just dont feel like posting about it…

for all you ppl that want a supercharger on you zx2 if you use a focus zx2 head the jackson supercharger will bolt directly on your car then the only thing you have to change is the timing belt tensioner.

It doesnt get in the way of the motor mount on the passenger side?