A4 shifting problem
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
A4 shifting problem
I got my tranny rebuilt and now, every once in awhile at 45 - 55 the car will lock in OD when I accelerate. The only way I can get it to downshift so I can gain speed and not vibrate the car apart is to just stand on the throttle for a second. Also, the car does not shift at the same points as before. I took it back and they tried adjusting the tranny and it shifts better, but not real good. Is there something I can adjust or should I take it to another shop?
TIA
TIA
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
The FSM has a procedure for adjusting the TV and throttle assembly. Make sure before you start playing to put a dot of paint next to the TV latch as a point of reference.It sounds like the TV needs adjusted out a hair to me.
Race Director
Joined: Nov 2000
Posts: 17,103
Likes: 39
From: stop the fun suckers
I got my tranny rebuilt and now, every once in awhile at 45 - 55 the car will lock in OD when I accelerate. The only way I can get it to downshift so I can gain speed and not vibrate the car apart is to just stand on the throttle for a second. Also, the car does not shift at the same points as before. I took it back and they tried adjusting the tranny and it shifts better, but not real good. Is there something I can adjust or should I take it to another shop?
TIA
TIA
Melting Slicks
Joined: Jan 2002
Posts: 2,238
Likes: 4
From: Milan
The speed should only taken in cosideration for the TC to apply.
The torque converter is also affected by TPS, but mostly by the speed read by the ECM.
For example my trans shift from 1 to 2 at 20 Kph(about 16 mph) at moderate throttle, but the rpm are just an hair on the high side. This can be compared to a car with less gear than mine. (I have a 3.45).
A car with a 2.59 and the same rpm as mine, can shift out of first at a higher speed.
The 2 trans shifts at a different speed, but both shifts correct.
-Beppe-
Melting Slicks
Joined: May 2007
Posts: 2,171
Likes: 1
From: Warwick RI
Measuring the shift points on moderate throttle with speed is an error.
The speed should only taken in cosideration for the TC to apply.
The torque converter is also affected by TPS, but mostly by the speed read by the ECM.
For example my trans shift from 1 to 2 at 20 Kph(about 16 mph) at moderate throttle, but the rpm are just an hair on the high side. This can be compared to a car with less gear than mine. (I have a 3.45).
A car with a 2.59 and the same rpm as mine, can shift out of first at a higher speed.
The 2 trans shifts at a different speed, but both shifts correct.
-Beppe-
The speed should only taken in cosideration for the TC to apply.
The torque converter is also affected by TPS, but mostly by the speed read by the ECM.
For example my trans shift from 1 to 2 at 20 Kph(about 16 mph) at moderate throttle, but the rpm are just an hair on the high side. This can be compared to a car with less gear than mine. (I have a 3.45).
A car with a 2.59 and the same rpm as mine, can shift out of first at a higher speed.
The 2 trans shifts at a different speed, but both shifts correct.
-Beppe-
If I gave bad advice I apologize
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Also, it doesn't downshift when I am around 50-60 mph.
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Race Director
Joined: Nov 2000
Posts: 17,103
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From: stop the fun suckers
Do you have your cat. converters still on the car.. also do you have an after market exhaust? Have you ever rebuilt the engine? Was your TC locking prior to the engine rebuild..
I ask alot of this because I've seen this problem before on another C4 and some of these things were related..
Also if your going between 50-60 mph and punch it (WOT) does it downshift? or does it not down shift when you moderately accelerate from those speeds?
Have you (or a previous owner) had the ECM recalibrated (or chipped in your case)?
I ask alot of this because I've seen this problem before on another C4 and some of these things were related..
Also if your going between 50-60 mph and punch it (WOT) does it downshift? or does it not down shift when you moderately accelerate from those speeds?
Have you (or a previous owner) had the ECM recalibrated (or chipped in your case)?