Cold Start Issues

**Crasher** · 01-11-2010,04:27 PM

The engine temp input from the coolant temp sender does not activate a coolant light, only if the ECU picks it up as being faulty will it bring on the MIL.

**Dino07** · 05-11-2010,05:06 PM

Where is the location of the sensor? I tried getting one from a local place today but they have so many listed. 2 for inside the coolant tank, 2 for behind the engine block.

I'm assuming it's the green one behind engine block?

**Crasher** · 05-11-2010,06:18 PM

Which year/engine?

**Dino07** · 05-11-2010,06:20 PM

2001 "y" asv

**Crasher** · 05-11-2010,09:54 PM

The coolant temperature sensor is in the plastic water housing on the end of the head above the gearbox, VAG part number 059 919 501 A.

**Dino07** · 06-11-2010,12:44 PM

Is there a replacement guide floating about?

**JimC64** · 07-11-2010,02:26 AM

Hey there, sorry to hear bout your probs

First off I'd like to say kudos to Crasher for his assistance......mega post count and always there tryin to help....nice one
I am Admin on one site and mod on another two so I know how vital regular posters / members / sponsors like this are for a forum to thrive

I have had similar probs with my A6 (07) and had many cold start issues and non starts too ( with the RAC called maybe 5 times in under 4 yrs )
Had the head replaced twice under warranty as thoughts of coolant loss were asscoaited with cracked head?
2 new batteries in that time also.
Most recently, haven't had any probs since although when cold it can still take a little longer to cough into life than I'd like, after the RAC came out last time.
They thoroughly checked the battery both at the terminals under the bonnet and at source in the boot....all seemed fine.
They suspected loose earth connections. I believe there was an earth strap underneath somewhere as well as a connector to the starter motor....Took these off and saw signs of arcing ( poor connection ) thoroughly cleaned them using wire brush / sanpaper and reconnected tightly ( they seemed a little loose also and I've not had any further issues to date.

This may not be your problem, but, possibly as a cheap potential fix that will cost nothing but time it might be worthwhile looking into

Either way, I wish you good luck and hope to be reading a post that tells us you found the problem and its now ALL good

**Dino07** · 08-11-2010,12:19 AM

May have come to a conclusion regardingn this.

Car wouldn't start today despite very slowly cranking over. Had the RAC over who jump started it. Tested the battery with their machine (Connected machine to battery, put on ignition, put on lights, switched off ignition and lights) and the battery tester signalled Replace Battery.

The rac guy offered a new battery at £110 but i decided i'd get my own.

What is the best kind of battery for these?

PS - I've got the coolant sensor already to replace. I have a go at it while waiting for the RAC but couldn't locate it anywhere!

**NickPicks** · 08-11-2010,11:17 AM

I'd go to a motor factors (allparts, euro car parts etc) for the battery. I'd expect it to be around £70. I'd go with whatever is cheapest and has a 3 year warrantee.