2003 Accord LX Sedan, 4cyl. AT, 130,000 miles, avg 19-20 mpg on 87 oct. Up to 32 mpg hwy.

Driving up an entrance ramp today on to I-70 when the engine flatlined at 2000RPM and would not accelerate further as if it were in a lower gear. Speed held at 60-65; relatively loud humming (like a baritone vacuum cleaner) on top of normal engine sound.

Pulled off, shifted into neutral and slowly applied the gas. Revved up OK to 3000 but got rougher than normal above that speed.

Got off at next exit. Accelerated fine on surface streets; revved freely above 3000. Normal engine sounds/behavior. Never happened before.

What's up?

 

I would stop by a parts store and have them check for codes.

When did you last change the spark plugs and air filter?