1G Knock Sensor Circuit Malfunction

[thejollyrancher]

Hey guys,

Being the absent minded klutz I am, I wired my AEM UEGO into my Knock Sensor pin instead of my FrontO2 and spent a week trying to figure out what was wrong with my readings. After i fixed up the wiring I've been getting a knock sensor circuit malfunction DTC.

My question: Could hooking up my wideband to the Knock Sensor pin screw up my ECU and be causing the DTC?

I don't exactly know the cause because I hooked up my wideband and got a used knock sensor from a 2G to replace mine at the same time. So it could be either be that I got a bad knock sensor, or that my ECU is screwed up because of my wiring mishap. Is there any way to tell if the ECU is okay? Visually it looks fine.

Thanks guys.

 

[donniekak]

You need a 1g sensor in that 1990.

 

[thejollyrancher]

Really? I was told by a few people a 2g sensor would work well. Are you certain?

 

[donniekak]

Yes, you need a 1g sensor.

 

[thejollyrancher]

Thanks for the info! Time to rip my hair out trying to change it.

 

[steve]

My question: Could hooking up my wideband to the Knock Sensor pin screw up my ECU and be causing the DTC?

The voltage output by the wideband could easily damage the input circuitry for the knock sensor.

The sensors need to match the ECU. Each generation has it's own characteristics and the ECU is designed to work with that model sensor.

 

[thejollyrancher]

Is there any way to test for damage?

 

[thejollyrancher]

Any ideas ?

 

[Phantom DSM]

The only time i have seen a 2g knock sensor in a 1g dsm is when using AEM ems standalone. Otherwise it will not work with a 1g ecu.
The 2g sensor is more sensitive and linear than than the 1g sensor. The filters are different and the 2g sensor will not communicate properly with your 1g ecu, thus Code 31 CEL.
Unless you have an Oscilloscope to test the sensor for other purposes on a 2g ecu, there is no point. You need to find a 1g knock sensor and torque to 14-17 ft/lbs.
You can trust the Donniekak and Steve on this.

 

[thejollyrancher]

Thanks. Im getting a 1g Knock Sensor today. I completely trusted them, I was just wondering if there's any way to test a circuit in an ECU by myself at home, just out of curiosity. Ill post again after I switch sensors

 

[thejollyrancher]

I'm still getting the code after switching sensors, looks like it might be an ECU issue. Thanks anyways guys!