S-Tronic 'Issue'
Posted: Fri Nov 27, 2015 12:18 pm
Been on the forum since July when I picked up my S4, but haven't really contributed much yet. Now I'm noticing something with the car and figured I'd ask those in the know.
Bit of background first I think. Car is an 09-plate (2009) S4 saloon that I picked up in July with 72k on the clock. As part of the deal I had the indi dealership do a gearbox oil change for both gearbox and mechatronic units. The car had been serviced about that time separately too. Right now, it's sitting with just over 77k and I do around 65miles per day, 5 days per week for commuting on the motorways (Edinburgh to Glasgow effectively). Car is standard without DRC or Adaptive Steering.
So, to the 'issue'. I've noticed more recently that when coming to a halt at the lights, typically first thing in the morning and when the car is cold, I get a jolt when the car downshifts from D2 to D1. I'm usually stationary when it happens (about 0.5s after actually stopping). It doesn't happen if I'm using the flappy paddles and already in D1. I use the Hill hold to keep the car from moving in these sort of situations to save blinding the person behind with the brake lights.
During the day the car doesn't move, and the return commute doesn't really have the start stop with lights and roundabouts when the car is cold as I leave Glasgow and may not encounter stationary traffic until the outskirts of Edinburgh so the car is properly warmed up by then.
Given it only happens in full auto, my gut feeling is some sort of software issue as the changes are smooth in manual and the Hill hold transitions are fine. I don't think it could be the mechatronic unit itself as I would have thought that the actuators would cause jip in both manual and auto if they were starting to die.
I'd get it into Audi, except that their £60 diagnostic for an hour initial offer was swiftly replaced with a 'We need it for 5 hours and after the first hour our rates go up to £100+', so it would be nearly £500 or a checkup. I have an RAC Warranty (came with the car), and I've got it booked in to a local specialist for a look-see on Monday, but does anyone have any thoughts?
Bit of background first I think. Car is an 09-plate (2009) S4 saloon that I picked up in July with 72k on the clock. As part of the deal I had the indi dealership do a gearbox oil change for both gearbox and mechatronic units. The car had been serviced about that time separately too. Right now, it's sitting with just over 77k and I do around 65miles per day, 5 days per week for commuting on the motorways (Edinburgh to Glasgow effectively). Car is standard without DRC or Adaptive Steering.
So, to the 'issue'. I've noticed more recently that when coming to a halt at the lights, typically first thing in the morning and when the car is cold, I get a jolt when the car downshifts from D2 to D1. I'm usually stationary when it happens (about 0.5s after actually stopping). It doesn't happen if I'm using the flappy paddles and already in D1. I use the Hill hold to keep the car from moving in these sort of situations to save blinding the person behind with the brake lights.
During the day the car doesn't move, and the return commute doesn't really have the start stop with lights and roundabouts when the car is cold as I leave Glasgow and may not encounter stationary traffic until the outskirts of Edinburgh so the car is properly warmed up by then.
Given it only happens in full auto, my gut feeling is some sort of software issue as the changes are smooth in manual and the Hill hold transitions are fine. I don't think it could be the mechatronic unit itself as I would have thought that the actuators would cause jip in both manual and auto if they were starting to die.
I'd get it into Audi, except that their £60 diagnostic for an hour initial offer was swiftly replaced with a 'We need it for 5 hours and after the first hour our rates go up to £100+', so it would be nearly £500 or a checkup. I have an RAC Warranty (came with the car), and I've got it booked in to a local specialist for a look-see on Monday, but does anyone have any thoughts?