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Discussion Starter · #1 ·
Has anyone else had this problem or got any idea what may be causing it?

Normally from cold my Tdi will take about 10 mins/5 miles before the gauge starts to rise. It goes smoothly from cold to mid position and stays there until the engine has stopped. Recently however I can at times go 7/8 miles the all of a sudden it goes up, it may fall again during a journey to the lowest position and pop up unexpectedly at any time. In the past I would have thought Temperature sender but i am not sure if the Pd engined cars have one, I had a quick look and couldn't see anything, Anyone any idea or is it a Dealer[}:)] job?

Cheers[:D]

Wallace
 

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NooNoo
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You need a new sender. About ?23 for part.

They are a common failure. Mine "pinged" about

for a week before I got it fixed.

[:)]
 

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Discussion Starter · #3 ·
Sounds OK[^], any ideas where it is located? Ijn the good old days whenI was a lad they used to screw into the cylinder head but I couldn't see a thing when I looked, could be my eyes right enough maybe i need to get them checked too[:I]!

Wallace
 

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I bought a new sensor a few weeks back. Cost ?25 from stealer. YOu need to note the colour of your current one as there is two types. As you look at the engine bay from the front its at the back right attached to the block. Its a bit of a pain to get too and your advised to drain some water out first to save it all peeing all over the drive.

I replaced mine but it had a plastic locating clip and i didn't seat it properly. It fell out along with all my water as i was driving along 30 minutes later. So be careful.
 

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Discussion Starter · #7 ·
Thanks Guys, I'll have a go once I replace my screwed up hub, see separate post.( "Iv'e really done it now." I think that's what i called it anyway)

Wallace
 

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Discussion Starter · #8 ·
Found the sensor today, it was black, new one purchased fron dealer, green replaces faulty black apparently, don't know if this means it's an upgrade or not. I will do the job soon, gauge didn't work at all today on one 14 mile journey but I need to get the wife's brakes sorted first..............Oh the headache!

Wallace
 

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Kev at JBS stuck a new one in for me yesterday.my new one green too it is an upgrade.old one was showing fault on VAG COM.

1.8T engine sensor is in different place,its at front on right hand side.

Kev showed me exactlly which one the sensor is if you need any help.

didnt drain any water just took off top of expansion tank.

jase...
 

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yea i have been having the same problem too. is this an immediate change or can it be done later and also is it doing any damage?
 

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Quote: posted by ppworld on 12/09/2004 14:34:52

yea i have been having the same problem too. is this an immediate change or can it be done later and also is it doing any damage?

mine been doing it on and off for couple of month.

just remember to give car chance to warm up before you boot it.

jase...
 

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Warming it up wont make a difference, if the sensor says its cold the ecu thinks its cold and its going to fuel it for cold ,ie excessivly, but the temp sender has 4 pins in it if you ever noticed, 2 for the gauge you read and 2 for the engine's ecu, so if ones faulty assume the others faulty too and if its over fueling its causing long term damage to your cat every time you drive it, or 'boot it' as its been so nicely worded.

Hope that helps your wallet, ?25 and a bottle of antifreeze is a lot cheeper than a new cat.
 

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Discussion Starter · #13 ·
Still haven't done it yet myself but I did think it wouldn't make any difference. Nearly got the hub problem sorted now so it's next on the list. 2 things I am not sure about, One is how does the clip that hold it in come off/on? and How did you manage to do the job by just taking off the expansion tank lid, surely coolant leaks out when you take the sensor out? I thought that was why you had to drain out some coolant before I start.

Thanks for all the replies by the way.

Wallace
 

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No more Mods....Yeah right !
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Discussion Starter · #16 ·
Did the job today, see what you mean now about the expansion cap but I idn't knoe that at the time, anyway only thing I maybe did wrong was to drain out too much fluid. It's quite easy really, I didn't even take of the engine cover, just pulled the clip straight down then let the coolant out bit by bit until it stopped. Then pulled out the sensor, disconnected the electrical plug, swapped the sensors and put everything back together, re-filled the fluid, I lost a small amount but had some spare anyway and that was that. No leaks or hassles, took the car for a longish run and then re-topped up the fluid and the gauge seems to be working perfectly again, Hallelujah!

Thanks to everyone for the advice.

Cheers

Wallace
 

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Make sure that the car is stone cold when you replace the sensor. Accidents have been known to happen.

When I replaced mine not a drop of fluid came out, much to my surprise and disgust having just brought a load of special VW coolant.
 

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Sorry to resurrect this post, but mine has completely died on me now and reading Weeloon's post I want to try and source the parts this weekend before I do any damage.

Does anybody have the part numbers for the sensor required for a 1.8T AGU.

Thanks in advance

Key
 

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First you need to check whether the connector housing is square or oval. Mine is oval (2000 AGU). Malta has a 1999 AGU with a square one.

In the beginning my car had a black sensor, p/n 078 919 501C.

I ordered a new one from the UK and got a green one 059 919 501A with a square connector.

Went to my local dealer and did a look-up on their system for the black sensor. Against my original number they had a listing saying that the part had been replaced by a newer part. Managed to get that newer sensor from them and it came with the round connector. The new sensor in my car now is light green, the square top sensor that came from the UK is dark green.
 

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I would check out what type of sender you have before going to your dealer. I even quoted the VIN when I got mine from the parts department and it was still wrong. Just take the connector off and check the shape.

I have a May 99 AGU and mine is the earlier square type.
 
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