1st off, sorry for the lengthy post, but I am completely stumped, and want to be as thorough as possible.
Daughters car developed a low pitch, almost hollow sounding knocking noise under any load the day after she dropped 5k on it. Not really any noise at idle. Only when giving it a little gas. Started mostly around the 2000rpm mark.
Timing chains and gears were replaced before she bought it, but I don't think they changed the cam phasers. At least they were not on the parts list the guy sent her.
Here's what's happened so far since I've had it.
I noticed the noise was only there when the belt was on, so I started checking pulleys, and the water pump was the only pulley with any type of play. Very minor, but there non the less.
Swapped the water pump. No change, knocking still there.
Changed the the belt and the tensioner, and the noise was gone. Problem solved, so I thought.
Started the car back up about 30 minutes later to test drive it, and the noise was back again, and now it is there at idle as well, only very very slightly.
Pulled the belt again, and the noise is now there without it as well, where before it wasn't.
I should add that after the new belt and tensioner, I did add a bottle of Berryman B12 to the tank not realizing that she only had a 1/4 tank in there. It also threw a P0324 knock sensor circuit code.
I cleared the code, and went out and bought her about 5-1/2 gallons of 89 octane, and a bottle of octane booster, which put it at a 1/2 tank, but no change.
Pulled the VVT solenoids. They were spotless, and the plungers worked when I applied voltage.
Broke out the stethoscope, and checked the whole timing cover, sounded smooth, no knocking/rattling type noise at all.
Thinking maybe a rod knock, I listened to the oil pan. No knocking noise at all.
I even listened to the cat, and the passenger side motor mount, and nothing.
There is only one place where I can hear the same noise clear as day, and that is the ac compressor. I can hear it loudly at the bracket, and very loudly at the compressor itself, yet it can't be the compressor, because the noise is now suddenly there even with no belt.
It also has multiple codes for a bad o2 sensor on bank 2, but I've never had a bad o2 cause a knocking sound.
Anyone out there with any ideas?
Not the best audio, but here is a short video. Notice it's mainly when throttle is applied in any amount.
Daughters car developed a low pitch, almost hollow sounding knocking noise under any load the day after she dropped 5k on it. Not really any noise at idle. Only when giving it a little gas. Started mostly around the 2000rpm mark.
Timing chains and gears were replaced before she bought it, but I don't think they changed the cam phasers. At least they were not on the parts list the guy sent her.
Here's what's happened so far since I've had it.
I noticed the noise was only there when the belt was on, so I started checking pulleys, and the water pump was the only pulley with any type of play. Very minor, but there non the less.
Swapped the water pump. No change, knocking still there.
Changed the the belt and the tensioner, and the noise was gone. Problem solved, so I thought.
Started the car back up about 30 minutes later to test drive it, and the noise was back again, and now it is there at idle as well, only very very slightly.
Pulled the belt again, and the noise is now there without it as well, where before it wasn't.
I should add that after the new belt and tensioner, I did add a bottle of Berryman B12 to the tank not realizing that she only had a 1/4 tank in there. It also threw a P0324 knock sensor circuit code.
I cleared the code, and went out and bought her about 5-1/2 gallons of 89 octane, and a bottle of octane booster, which put it at a 1/2 tank, but no change.
Pulled the VVT solenoids. They were spotless, and the plungers worked when I applied voltage.
Broke out the stethoscope, and checked the whole timing cover, sounded smooth, no knocking/rattling type noise at all.
Thinking maybe a rod knock, I listened to the oil pan. No knocking noise at all.
I even listened to the cat, and the passenger side motor mount, and nothing.
There is only one place where I can hear the same noise clear as day, and that is the ac compressor. I can hear it loudly at the bracket, and very loudly at the compressor itself, yet it can't be the compressor, because the noise is now suddenly there even with no belt.
It also has multiple codes for a bad o2 sensor on bank 2, but I've never had a bad o2 cause a knocking sound.
Anyone out there with any ideas?
Not the best audio, but here is a short video. Notice it's mainly when throttle is applied in any amount.
Last edited:
