OK age old prob my 2001 a6 4.2 is I guess in limp mode and just not sure what to do? reverse is fine , tcm appears to be fine no water or bad connections , is there any down and dirty way to verify if its the transmission Vs, the Tcm? my mechanic ran diagnostic said wrong gear ratio or something similair ?
PLease Help !! ps first post if in wrong place please advise thanx

 

first, how do you know your transmission is in limp mode? If you have reverse and nothing else you either need fluid or a new (rebuilt) transmission.

if you took it to a mechanic why are you asking questions here? if your mechanic can't/wont tell you what the "diagnostic" said, exactly, or tell you what the problem maybe it is time for a new mechanic. not picking on your guy, per se, but....

good luck

 

well that is why i picked the car up lol the mechanic has worked on all my cars in the past but this might be out of his scope?, the car does not seem to go into 1st or 2nd gear if i put it in drive it feels like it goes into gear for a few seconds then comes out, it will creep forward and slowly accelerate and when going 40 mph or faster drives fine, or reverse at any speed. if i put it in drive quickly accerate it will thump and highlight the gears on there dash

 

limp mode defaults you to third gear only and highlights the indicators on the dash.

you need to see if you can find a vagcom (VW/Audi specific code reader) and see what codes you can get from that. there is a sensor in the body of the transmission (sorry the specific name escapes me at the moment) that may need to be replaced. when it goes bad it gives the symptoms you describe. you may also have a bad TCM (vagcom scan should help). you may need fluid (there is no dipstick). the fluid filling procedure requires you to monitor the temperature of the transmission while you fill it. you mechanic should be able to remove the transmission fill cap and determine if the fluid is low (should be close to even with the cap). could be a torque converter or you may actually need a new/rebuilt transmission

-not an expert just an enthusiast

 

i have a vag-com on the way im just not sure what good it will do if i get the same data that the mechanic did , po730 incorrect gear ratio, from what ive read you can get that code for many reasons- will this device actually deduce if it is the transmission, a sensor ? or tcm?
thanx

 

P0730- could be bad news, not a sensor problem, not a TCM problem

either a fluid problem or your trans is shot (mechanically)

 

Possible causes- Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Shift solenoids harness or connectors
- Transmission mechanical problems
- Transmission hydraulic control circuit
Tech notes
Start by inspecting the transmission fluid level and condition, and change fluid if necessary.When is the code detected?The TCM has detected that the transmission is trying to mechanically shift to a lower gear than intended

P0730 AUDI Description
This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows:

Torque converter slip ratio = A x C/B

A: Output shaft revolution signal from speed sensor (revolution sensor)
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes

If the actual gear position is higher than the position supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.