Quick question about what might be a bad knock sensor: I know that getting the det code means either something is wrong with your wiring or knock sensor, also for us with a gti-r I know it changes the timing causing us to run rich and if we have the stock boost solenoid it drops it to base boost. All these is what my car have started doing. And I did a code check and I am getting a code 34: det sensor. My question is this, I cleared the code and started the car up and let it idle for a bit. Checked for codes, nothing. I drove her around keeping low on the rmp (no boost). Checked the ECU, no code. Then drove her normal and it threw the code and went into safe mode again. After trial and error I notice I only get the code when driving her hard and boosting. So my question is this: anyone else have this problem with their knock sensor? Is this normal? I thought they just went bad and always threw the code. Any insight would be nice before I drop the money on a new one.

I have checked all the wires and connections, all is in working order. I haven’t taken the sensor off to check it yet, I just thought it was odd that it only does it once I drive it hard.

Also, I don’t hear detonation or else I would obviously know what’s going on… except that it was throwing the code for odd reasons then.

Maybe you're getting detonation? Maybe slight rod knock is setting it off? Check the resistance and see if its within spec w/o removing it, its easy.

I almost wish. Unless I have the super silent engine of doom, which I doubt seeing that GTi-Rs are known for being the loudest, I don’t have any rod knock or detonation. Besides, your ECU only throws code 34 when there is a problem in the circuit or with the sensor, not when it is set off. But when there is a code 34 it still sets the car into safe mode just to be safe.

I do need to still check the resistance. I just fear it will come up fine since it only seems to malfunction on heavy rpms.

I've been reading over the forums overseas into the issue and I've found two others that have had the same problem with the code only being thrown when the car is pushed. So I'm thinking I might just have a rare case of a messed up det sensor that only goes fault on heavy rpms. But any other input would be nice too.