While changing the oil on my civic HX I noticed a sensor that had no plug in it on the back of the block. I looked all over but did not see a plug for it. Anyone know if this is normal? It looks like a knock sensor and is blue.

 

Post a picture.

 

Does your oil pressure indication light come on, on the dash when you turn the key to II?

 

Is yours a 5 speed or CVT? Look like this:



Or this

 

Mine is 5 speed. It is not the oil pressure sending unit- no CELs or codes.


Thank you all for responses they are much appreciated

 

is the engine in it the orignal engine? sounds like a knock sensor

 

Yes original engine car has never been modified or anything of that nature- I really think its a knock sensor but am confused why there is no wiring for it? The plug also appears to be quite clean which makes me believe the plug wiring fell off recently but it is no where to be found...

 

An unplugged knock sensor would throw a CEL code. Does the CEL work? What ECU do you have?

 

Have you had the car since new? Only the CVT's had the knock sensor according to Majestic website.

 

I think you are correct.

 

Just wondering if that is a knock sensor if someone swapped blocks (or engines) out at some point in time in the car's history

 

If the block was swapped, then the VIN riveted to the block wouldn't match the car