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Hi all,

Have been meaning to change the sensor for a while since the guage developed a mind of its own. Then last week it developed the dreaded warm-starting problem.

Got round to changing it this evening (black one came out - green one went in) and managed to slip in the afterun sensor whilst the bonnet was open. Big thanks to Quantumjohn (me bro - so not an uncompetitive labour rate too) for the help and almost giving me his mini-maglite in the process.

Car now runs smooth as a button and needle is back where it belongs. Not only that, but gear changes are smoother and throttle response is much quicker too. So all in all - another extremely pleased S4 owner! And if it needs doing, and you're searching for water temp sensor changing - get it done!

Cheers

Hi Travs,

Was the temp sender particularly difficult? Mine is exactly the same, want to have a crack at it myself but everything looks a bit expensive to break!!

Thanks in advance

Ross

1999 S4 btw

Hello mate,

There is a flexi-pipe that at the top of the engine at the back leading from the y-pipe (silver metal y bit at the top of the block), leading from the air filter housing. About a foot long and 4" in diameter. Take that off and you can see the sensor sticking out of a holder at the back of the engine on the driver's side. A plastic clip, like a circlip, slips in the side of the housing holding the sensor. Then everyone states that the sensor
is seized in but thankfully mine just popped straight out. If so, I'd recommend getting a set of long-nosei pliers (or anything that will fit in the gap) and giving it a twist and pull.

The worst aspect of it is the scraping on the knuckles and back of the hand but technically there is nothing difficult to do and nothing that you'll break as long as you're not a bull in a chinashop.

Let us know how you go fella. Whereabouts are you?

hi Travs,

Thanks for the info will have a poke round at the weekend and see what i can find! Although I busted me hand up tonight so dont fancy scrapping me knuckles quite yet!!

Cheers for the info will let you know how it goes! Hoping it solves the problem.

Im in Herts btw

thanks again

Do mate - always good to know how people get on - fingers crossed its as straightforward as mine was....

2 min job

Hmmm....well had a go found it etc....er and failed miserably. Its such a simple job but mine seems to be welded in, quite obviously shagged, all corroded etc!

Couldn't get the plug off the top, tried from the bottom up and the retaining broke (last bit of that still stuck there)!!

Im so annoyed but ive given up...what a hopeless DIYer!! Will book it in next week and give someone else the joy of fighting with it!

Mine was properly seized in aswell

There's a knack to getting the connector off.

Once that was off, i got a extra long nose pliers on it, twisted it (totally mashed the sensor at this point, so no going back now!), and then kept on twisting it, whilst pulling it aswell. Got it out in the end

When i did mine i sprayed the area in WD40 and left it for 5 minutes, it then came out very easily.

Mate,
Sorry that yours has been so much trouble. I must have been bloody lucky. I'm sure it'll be sorted soon though.

Gonna have a go again tonight...will use a bit of WD40 to ease it. Does coolant pis$ out when you do it or can you take your time?

Loosen the radiator cap first to release the pressure (careful if hot obviously) Coolant wont leak much after that is done.

Plus gas, much better than WD40, a proper penetrating oil..... been going for years and still a good one http://www.pvrdirect.co.uk/productinfo. ... Ref=PLG809

Darren

Mine was cold - had been sitting there all day so there was no pressure. The sensor receptor's are high up the system so there is little, if any affectual, gravitational pull/push on the water so none came out with mine.

Didn't think to take cap off. Although its a good idea to realease any pressure, I wonder if that might also give atmospheric pressure a way in from the top (like sucking liquid into a straw and putting your finger over the top stopping it come out the bottom scenario).

Bought a bottle of G12+ coolant (the pink stuff - funky colour) as I'd read its a good idea to top the receptor up just so there isn't an air bubble put into the system - if you're going to do that you need a funnel to be accurate and its literally only 20/30ml.

Ross - whereabouts in Hertfordshire are you. I've got an exam tomorrow morning so don't want to do much tonight but if its still hassle, I've got nothign after the exam tomorrow and it finishes at 1:15 and I've got nothing on after that if you want a pair of hands?
I'm Essex so its not that far (depending on which part of Herts of course!)

Appreciate the suggestions guys - thanks everyone.

Travs - thanks for the kind offer mate appreciate that! Yesterday was a bad day was due to go out and was rushing to get it done. Pretty sure if i take my time tonight and get some pipes out the way ill get the sod! Such a simple job just a swine to get to! Ill let you know how i get on - if its a no good then help would be much appreciated!

Am home at 4.30 today so will get straight on it while we still have the weather! Will let you know - once again appreciate the offer! Good luck with the exam mate!