How serious is this issue? (2000 A4 low rpm shudder)

[Dman8777]

My in-laws have an A4 that I drive every once-in-a-while and it shudders consistantly under acceleration between about 1500 and 2200 rpm. When the engine is spinning faster and I accelerate, there's no problem. It's a 1999 or 2000 (nobody seems to know, the cars been passed around the family) with close to 200k km on the odo and a 1.6l engine.

The shudder is low-frequency but very noticeable. I feel it it in the steering wheel, the shifter, the gas pedal, the seat, etc.

I just want to know if this thing is gonna die suddenly someday or if it's an issue that can be ignored.

Google didn't turn up much info and I've told the in-laws to get it checked out. However, because my mother-in-law is the the primary driver (and clueless about cars) she doesn't think anything is amiss. If I had the money, I would take it to get checked out myself but funds are tight unfortunately.

 

[manimal]

Could be transmission or inner axle joint failure. Can you get the front end of the car up and check play on axles?


Has there ever been any transmission work done on the car? Try driving the car uphill and see if it worsens the problem. If it gets worse then it may be the axles. A failing axle will vibrate under acceleration because of the increased torque. when coasting it should go back to normal if it is a axle at the onset of failure.

Ask a friend with a lift to check it for you.

 

[Dman8777]

If it was an axle, would it be rpm-dependent? We don't have that many hills around here but I don't seem to recall the problem being any worse on ~10% grades.

 

[tbike06]

Engine mounts?

 

[Dman8777]

It definitely feels bad enough to be something like the engine mounts but then why would it be confined to just that rpm range and only under acceleration?

It feels like fuel delivery isn't adequate, like maybe the fuel-air ratio for the rpm range is out of whack...