Sensor

[Tanner]

I was dewinterizing everything and snapped the wire off on my knock sensor. I had way to much other crap going on to mess w/ fixing it at the time. Does the knock sensor unplug anywhere or does the wire go straight back to the ECM. Can it be soldered back, or like I said... is there a plug that I can unplug it from and just replace it quickly enough?

Better question is, will the MP 340 still run w/o it like some ECM's will allow, or is it programmed to go into limp w/o it?



Yes I stole the pic from CHP

[chpthril]

The black plastic portion that the blue wire is attached to is a connector that snaps on to the Knock sensor. It has to finger tabs that you squeeze together and then the connector will slide off. Sounds like you probably broke off the male portion witch is part of the sensor. If so, then you will need a new sensor.

The ECM sends a small amount of voltage down the blue wire. The internal resistance of the sensor keeps that voltage at a particular level. When the wire is off, sensor goes bad, etc, that voltage level changes and the ECM interprets this as a problem on the circuit and sounds the alarm and goes into Limp Mode. The reason the sensor has such a higher priority in a boat v's a car, is because you will probably never hear the engine "spark knocking" until it's too late and it's eaten a hole through a piston, etc.