Why when i lightly accelarate, the car vibrates a little and i can hear the engine kinda like a humming?

Question

but when i push it a little harder it goes away, its only at very light accelaration its a 2000 Jaguar xj8

it seems to be at the start of every gear and not the end of it

Answer 1

The early Jaguar 8 cylinders had a problem with timing chain tensioners. You may be hearing your tensioner beginning to give it up. I'd suggest having it checked by a reliable shop. If you lose the tensioner, you lose the motor.

Answer 2

You either need a new set of spark plugs or a transmission service. You can get a rough low idle if your plugs are way out of spec's. Might do a throttle body cleaning, too.

I love those automatic transmission additives. They can make that typical tranny noise go away. There's one that is sold under the Slick 50 brand and another at AutoZone that is blue in color and they can knock that annoying noise down or make it disappear.

Good Luck!

Answer 3

Thats normal, every car with an automatic does it. It has to do with the gearing of the car, going say 30mph, the car will be in 3rd gear, which is a little too low so the engine is lugging a little.

Answer 4

Engines (and whole cars) have their own resonant frequencies, where they make more noise and vibration. The Engineers do their best to limit these resonant frequency situations to rpms or conditions that exist least often.

There are a lot of different things that can cause what you describe, but almost none of them are of any concern at all.

Answer 5

Sounds like your motor mounts might be getting a little mushy.

Answer 6

the hum is maybe the trannie, shake could be the same,trannie or drive shaft