Desperately need advice

I have 83,000 miles on my 5 speed and lately it has been losing power briefly then surging. It only seems to happen when I’m on the highway. It seems to be getting more frequent. I have not noticed it using any more fuel than before. Also the RPMs run at about 3200 and the engine noise seems louder than it used to be. I’ve noticed too after driving into work or home (about 35 miles each way) the engine has a high pitched whirring sound (almost like a jet engine powering down?!). Any ideas what it could be?

There could be a number of causes; a partially plugged catalytic converter, a collapsed exhaust pipe, a partially plugged fuel filter, a fuel pump in the process of starting to fail, an air conditioner compressor that is seizing up.

You need to take this car to a good mechanic before you end up with some very expensive repairs.

From what you describe there is not enough info to pin down the cause of the problem.

look for a vacuum leak, I do not know your car year, make or model. By noise, do you mean pinging ? It is at 3200 rpm at park and warm up ?

when I first start the car the RPMs are about 1000. When I first got the car I couldn’t hear the engine running but now it seems louder. That’s not a very good description, I know. It isn’t a pinging sound at all, just louder than it used to be. My car is a 2007 Mazda 3i 5 speed

No intent to offend or anything, but count the gears as it shifts and make sure it goes into 5th. If it hangs in 4th, noise and rpm’s will be high.

The only reason I ask is because you did not specifically state you were sure it shifted into 5th on the highway. There is another thread I just saw where someone wanted help to find out why his car hangs in 4th.

no offense taken at all. I wish it was something that simple but unfortunately I am sure I am in 5th gear. I’m not so much worried about the 3200 RPMs as I am about the hesitation/surge. I’m going to try a fuel system cleaner tonight when I fill up the tank but I’m pretty sure that won’t do anything. I’m worried about O2 sensors, fuel pump, fuel injector or catalytic converter problems. Or some kinda combination of all of the above.