2010 Audi S4
The engine will jump up and down around 200 rpm when running at 2000 rpm. I had the car at the dealer and they said this is normal. I know that for the first 2 years that I owned the car I never felt this happen. When I am driving at a constant speed I will feel the car surge forward due to the rpm jump. Has anyone seen this problem?
What can I do to correct it?
There seem to be a service bulletin that just came out and not too many people know about it. I can't even get it but there is talk about it on Audiworld.com Forum. It describes a condition of engine surging while cruising at highway speeds. That is where you are seeing the surging about 2000 RPM's.
The following service bulletin segment is from AudiWorld.com, The only place I was able to find it. I still don't have a bulletin number it came out with this title (Shudder or RPM fluctuations while at cruising speed Release date: Feb 3, 2012).
I hope this helps you out.
The service bulletin they are describing a slipping torque converter slipping at highway speeds.
On a scanner, the MVB for TCC should show "OFF" and "ON" (or "open" and "closed"). If it reads "CNTRL" constantly, it is the converter. The ECM/TCM is commanding full TCC but not "seeing" it.
1. Check and verify that the software is at the highest level using TSB 2028053, 37 TCM software update for downshift concerns or 2028279, 37 Shift concerns when slowing vehicle. Also, check that the fluid level and condition is clean, full, and matches the required color per the applicable TSB.
Tip: If needed, update the software of the transmission and change the fluid before proceeding with this TSB.
2. Test drive the vehicle to verify the concern is present.
If the concern can be duplicated, verify there are no fault codes stored for misfires and watch the Measure Value Blocks in the ECM to verify no misfires are seen when the condition is present.
3. Check MVB 7 from the TCM. Verify Field 3 is reading control and record the slip count from Field 4 while the concern is present. The slippage of the TCC should not exceed 120 RPM in MVB 7 field 4 while the converter is in control mode. The RPM surge should coincide with TCC slippage. If this reads higher than 120 RPM, the torque converter should be replaced.
Tip: The TCC slippage will vary when in open TCC mode and should read 0 when in closed TCC mode, this is normal. Replace the converter for high slippage when the TCC is in control mode (above 120 RPM) or for any slippage when in closed mode (MVB 7 field 4).
Tip: It is not necessary to receive a Repair Authorization to perform this TSB.
2008 A4 2.0T Avant APR I