eliastfk

my 98 a4 2.8 30v quattro starts to shutter between 1400 and 1500 rpm in all gears, once out of that range the shutter goes away. I do have a check engine light on however, n it was diagnosed as "secondary intake" (which i suspect and was told was my mass airflow meter) o2 sensors and coolant temperature sensor. I would like to know if any of the problems stated above would cause the car to shutter/vibrate at the stated rpm range.

Old Dog

Start with your Mass Airflow sensor which is located by your airbox. This sensor measures air flow and provides a proper fuel/air ratio for the motor. You may be overloading your motor with too much air if the sensor is garbage . You get a shudder since the motor won't use all this air under low rpm . However, once you increase speed the motor requires more air, so then it works okay.

It might be your problem.

ThomasB5A4

I am having a similar issue with my 98 2.8 FWD tip.
I replaced the Mass Air meter, plugs, wires, coils, even replaced trans fluid and filter and 2 injectors! I still have a shutter in that rpm range. Doesn't mean it is the same issue, but I thought I would share. The trans filter and fluid change made the most notable difference but I still feel it.

Does yours still shutter if you give it more gas...say from a stop light?

eliastfk

Mine only shutters at that specific rpm range, it's normal up until then regardless of how hard i accelerate, and its perfectly fine once i am out of that range. It does it in all gears though so im pretty sure its not a transmission problem.

atrain5600

2005 A4 Cabriolet 3.0 V6 quattro with 80k miles.

I have a similar vibration at around 1400-1500 rpm. It occurs in neutral or while driving. If I'm rolling it actually seems louder when I corner to the left.
I have a dealer service appointment next week and will post whatever they find out.

thefish

My best guess would be the throttle body. I had the exact same problem on my 99 30v. While driving the problem is non existent. As soon as I am idling and rolling though, or light on the throttle I would get a horrible shudder.

I figured I would start as cheap as I could. Got some seafoam, ran it through my crankcase, vacuum lines, and gas lines. Also removed the Throttle Body and found carbon buildup. I didnt think there was enough buildup to affect the idle. Sure enough though, as soon as I did all of this stuff she run awesome now.

Seafoam - $8.00 Autozone
Clean Throttle Body - PITA but free
Smooth running car - Priceless

eliastfk

I ran a throttle body cleaning agent directly through the throttle body and the problem continues. My check engine light is on because of it. The codes that come up center around my intake/o2 sensors. I was told to replace my air filter, which i will do next because its cheaper. I already replaced my Mass Airflow Meter and it made no difference. I was also told that if it wasnt air filter that it would be my catalytic converter or o2 sensors.

Reggie

You guys might think about trying a can of BG44K in the gas.

1999Audi

Did anybody fix it, I need to know because I have the same issue

atrain5600

Mine was fixed by replacing a pipe in the power steering. It may have just been air in the line, but there is a tech bulletin about a pipe or hose that was too long and caused the vibration.
Completely counter-intuitive, but it worked.