The noise usually happens when the car is started after sitting for a long period of time. The knocking usually stops after a couple of miles. This morning however it did not start until I drove around 3 miles then it lasted for around 3 or 4 minutes. The knocking is coming from above and behind the drivers side rear tire. If I listen from the outside this is where the sound comes from and if I open the rear hatch the sound comes from inside the plastic moulding on that side of the car.
This is not an exhaust issue. This knocking happens almost like a clock ticking, every second no matter what is happening. You can be going over bumps or sitting still. It does not skip a beat or change the frequency. I know a bit about cars and I know that this does not have anything to do with the exhaust. Any other ideas?
I DONT KNOW OFF HAND OF ANYTHING LOCATED IN THAT AREA THAT IS MECHANICAL THAT COULD CAUSE THIS NOISE LET ME TAKE A LOOK THROUGH THE SERVICE MANUAL TO SEE IF THERE IS ANYTHING I CAN FIND. DO YOU HAVE REAR HEAT AND AIR CONDITIONING?
Yes and I looked up at that area today and there are air conditioning lines running up into there where the knocking is coming from.
OH THATS GOOD THE FRONT AC SYSTEM USES A FIXED ORFICE TUBE TYPE SYSTEM AND IS A PRETTY QUIET SYSTEM THE REAR AC USES A THERMOSTATIC EXPANSION VALVE AND THESE HAVE BEEN KNOWN TO MAKE NOISE WHEN THE AC SYSTEM BECOMES A LITTLE LOW ON CHARGE. I WOULD START BY HAVING THE SYSTEM RECHARGED THIS SHOULD CURE YOUR NOISE. GOOD LUCK. YOU CAN CONTACT ME IF YOU HAVE ANY MORE QUESTIONS. FREDERICK