Rough Idle / Difficult cold start

[Winners]

Hi All

Anyone help. My Mrs took her A4 Cab 1.8T to Halfords (I know!!)the other morning when she was stuck with noisy steering, after I'd already gone to work. They checked and repaired a faulty PS pump pipe. (£100!!!!) That'll teach me to not be around! Anyway since then the cars been struggling to start / idle after a cold start in the morning. After warming up it's fine for the rest of the day. Is this coincidence or has a sensor (CO2?) been caught during the repair. I don't know what's in the region of the PS pump.

Thanks

MArk

[white.akita]

get the fault codes read, it could be many things.

[pauldazzle]

Coolant temp sensor would be my guess, especially if it's ok when up to normal temp. Possible that Halfords have disturbed the CTS connector, but more likely the CTS is faulty & it's just coincidence that it's failed at the same time as having the PS pump replaced.
CTS has 2 outputs 1 to the temp gauge & the other to the ECU. It's very common for 1 output to be working correctly while the other isn't. If the ECU thinks the engine is hot when it's actually cold it won't fuel correctly hence the poor idle & cold start issue. VAG revised the CTS as the old ones kept failing. Unfortunately CTS failure doesn't always throw a fault code. If it's gone open circuit or intermittent it will, but if the ECU is still getting a reading it won't throw a code.