My engine... it don't sound right.

[haux]

A few weeks ago I had to drive about a hundred miles back home on a bad spark plug. Ever since then, I've noticed that my engine sounds... off. I really cannot figure out how to describe it. But, it also seems that the RPMs are going up way too high. Regular acceleration (...regular for me) shoots the rpm up past 3,000. I don't remember this happening before.

The new plugs I put in were Bosch, because that's all I could get at the time. I thought maybe something was weird about 'em, or that I had maybe put one in some weird way the first time. So, today I replaced them with Denso's from the dealership. I haven't noticed much improvement. Yesterday I also cleaned the throttle body with carburetor cleaner, and replaced the air filter.

I still think the engine is sounding weird during acceleration, and I feel like the RPMs are going up way too high.

Any ideas what could be going on?

[maxima1274]

You sure have a lot of miles lol

[ghettosled]

even though the engine is spinning faster, does is it running smoothly? is your AC on?

[fenixus]

have you checked spark plug wires? when did you replace them for the last time? i was having a somewhat faulty wire before and over time noticed louder engine (accompanied by higehr RPMS) when accelerating.
after tune up (plugs, wires, fuel filter) it's gone, now accelerating at quieter pace, lower RPMS, same speed change. it's possiblt that one of your wires is not providing enough spark for one of cylinders so when hitting the gas pedal it makes it accelerate on 3 cylinders?

i'm not a mechanic, but tune up improved my ride significantly.