MIKE DAHLGREN

I have a 2007 RDX. I'm getting a P0325 and 77 drive train. I know they go together. I replaced the knock sensor with cheap one from internet cleared the codes and didn't get one for about a week, then back to getting the codes every time I drive. Not sure if it has anything to do with it but I have absolutely no heat, maybe bad thermostat. Possibly bad thermostat could be causing both problems? Any help would be greatly appreciated, thank you in advance!!!

Lc46em

Hey a bad thermostat would not cause you to have no heat inside your car. Things to check would be low coolant or a coolant leak as coolant runs through your heater core which provides you with heat if you have coolant and no leaks next step would be if you are getting any air cold or hot when you put the climate control to on. If you are getting air my money would be to flush out the heater core and add new coolant and bleed air from system.

Lc46em

As far as the knock sensor code if you installed a new sensor and it came back again I would double check the wiring to the sensor could be a cut or broken wire. Someone's the pins which hold the wire in place get loose and cause I bad connection and can cause your problem

Ryan Fry

Question. I too have an 07 RDX which has been trouble free until the dreaded P0325 showed up. I replaced the knock sensor and the code went away for a couple months. Now its back. The knock sensor was an OEM decent looking part, so I am doubting that I have a bad one. I am wondering if this car really needs premium fuel and if regular unleaded (88 Octane with Ethanol) as opposed to 91 with no Ethanol would cause the same symptoms? I am a knucklehead, but just wondering...

Tomtwtwtw

Octane is simply a resistance to detonation/spontaneous combustion. 88 octane gas with ethanol is still 88 octane (unless you are adding ethanol yourself afterwards) and should be avoided in the first gen RDX for any extended period of time. Likewise, any version of 91 should be sufficient, whether or not it's an ethanol blend. If you're still getting consistent knock issues while running 91, maybe try other stations/brands if you haven't already done that, and if still an issue then it could be some other problem with the car.

Ryan Fry

That makes sense...I know that lower Octane can produce knocking and rough running, but the question is - would it foul the knock sensor or bring up the P0325 code? or is it totally unrelated?

Tomtwtwtw

No, the sensor itself would not be ruined from using lower octane gas.