My engine light went off when I started using high test in my miller cycle engine. Been off for a while now but I noticed that it is more sensitive in the summer months. It seems that if I really get on it, it will set the light off, and if I take it easy as not to rev it high or go over 3k rpm it will turn back off. Why would that happen?

 

Plz get some codes..not enough info to try & help u ...

 

Think it is a PO 325

 

well, that for sure is knock sensor. you might want to try several tankfuls of gas with a really good fuel SYSTEM cleaner. not just injection, SYSTEM. you may have some carbon buildup in the combustion chambers, and if so, then it might be detonation or pre ignition. if you can get it cleaned up, that might help. but i think the sensor is fubar. they kinda die over time, and get sensitive. i think you will have to change it. and, it is under the supercharger. BIIIIG job. special tool needed, to install the sensor. you might be able to get it off with a normal socket, but you destroy the lead. to install it, you need a socket that has a groove cut in the side, just like an oxygen sensor socket. one possible solution is to install the sensor somewhere else on the engine. the connector is easy to get at, and you can either find another place to screw it in, or make one. then you dont have to pull the compressor. but it wont do as good a job because it needs to be close to the crank and rods.