Nissan Repair Questions? Ask a Mechanic for Answers ASAP
My engine makes a loud noise, sounds like a race car. Its when I start the car and especially when I accelerate its real loud; and when I put on the AC what is this noise?
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This noise you are talking about, does it seem like it's in the front of the engine? Does turning the AC on and off change it's pitch?
Yes, when I am at a stop I don't hear the noise. If I turn on the AC I hear the noise and its more constant but its gets louder especially when I accelerate and it does seem to be in the front. I was going at about 70 miles an hour for about 10 minutes, then I started to hear the noise. Before that it was fine. I just recently replaced the engine manifold gasket and the knock sensor.
It sounds to me like it could either be an AC compressor or the drive belt pulley. If the noise is only present when the AC is on, I would lean towards the compressor making the noise. If it's constant, and more pronounced when the AC is on, then it could be a belt pulley. I would look into those two items.
Hope this information helps. If you have any more questions, please feel free to ask. Thanks!
Could any of those be a result of me going fast cause it started making that noise after that; because when I go over 65 the car shakes also.
I don't think going fast is the cause of it. Does the noise change it's pitch the faster you go? Does the noise go away when you turn the AC off?
The noise is more constant with the AC on but if I turn the AC off the noise is there only when I acelerate. It gets louder the more I give it gas when I'm driving.
The shaking I would think is a tire balance issue. The noise I would think is a possible compressor going bad, or a belt pulley. If I heard the noise, and was able to test drive your car, I would be able to find it easy, but over the net it is harder and I can only give you a general location to check into. Thoughts are my thoughts on what I think your noise could be.
If you have any more questions, please feel free to ask. Thanks!