Ghost foot on the pedal

You know this feeling: Imagine the cruise control is on and you go down a big hill. The car accelerates past the point the cruise is set on and so the cruise stops the car from exceeding that limit. I don’t know if it is accomplished by lowering gears or by using the brakes, but you know how it feels – like there is a ghost foot on the brake.

We were on the toll road Friday doing 78 (just under 3 rpms) and that started happening. We turned the cruise off and accelerated back to 80. For miles, it felt like a ghost foot on the brake. The cruise was off. We accelerated and the car chugged as if we were hitting the brake. We pulled over and checked the oil and the engine in general – nothing. Back on the road, it continued to do it for another 15 minutes then stopped. It didn’t do it again until I was going 60 on the way to work Monday morning, and it did it all the way there (9 miles). Not in 20-40 mph traffic on the way home, not yesterday morning, but this morning only twice.

Any ideas? It has 166,000 miles and has had regular oil changes and service including recent timing belt and alternator.

It’s hard for me to picture exactly what you’re describing.

If you’re saying that the engine itself hesitates (and the RPMs drop) even when you keep your foot steady on the accelerator, then possibly you need a new fuel filter or your fuel pump is dying. A mechanic can test your fuel pressure easily.

If you’re saying that the car is downshifting, so that the RPMs jump up, then my first question is if the transmission fluid is at the right level and if the transmission has been maintained according to the owner’s manual.

Is the check engine light on? any codes?

When it was sluggish, did the engine rev up like it was in a lower gear?

I would not drive it in this condition, except slowly to a repair shop or dealer.

Brand, make, model, year?

“the car chugged as if we were hitting the brake”

Does your car usually “chug” when you hit the brake?
That could indicate a vacuum problem related to the power brake booster, or it could relate to a dirty Mass Air Flow sensor (MAF), or it could be the result of a different problem.

When you say that the car “chugged”, do you simply mean to say that it slowed down, or do you mean that the engine is actually “chugging”?

If it happens again, get out and carefully (don’t burn yourself) feel all 4 wheels. If one is significantly hotter than the rest you have a stuck caliper that’s applying braking force without you stepping on the pedal.

Excellent advice from Shadow.
The caliper is probably sticking intermittently, based on your description. Any competent shop can check this for you by simply trying to turn the wheels with the car on a lift or, if it isn’t sticking, checking the pad thicknesses. A sticky caliper will cause one pad on the affected caliper to wear much faster than the other.

Make/model/year?

When you say it was “chugging”, that sounds like a misfire. If so, the check engine light should be on. Is it?