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Discussion Starter · #1 ·
My gauge rises as normal and settles at 90... When i plug the car into vagcom the coolant temp settles at 100-102 degrees and slightly decreases to maybe 98 whilst driving. Aircon lowers the temps a little bit but not enough.

Been told its likely the pump may have lost part of an impellor or something... hence not cooling properly. When revving the car water is pushed into the expansion tank as expected so i guess its not ''completely'' broken...

Others advice and input is appreciated :)
 

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TEAM 88 MOTORSPORT
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sounds perfectly normal to me...what makes you think there is a problem? vag-com gives a true reading of the temp. The guage on the otherhand will always show 90 which in actual measurement can be up to 15deg more or less[C]
 

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Discussion Starter · #3 ·
Well i know my old corrado used to get very hot 102-106 whilst driving and anything to 115 stood still.

I done a few logs on my PD130 and that didnt go past 90 on a run averaging 86-88 degrees. I cant see the AGU wanting to run hot?
 

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Discussion Starter · #5 ·
I personally have no idea? theyve never come on unless i use airconditioning which activates the front fans...
 

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TEAM 88 MOTORSPORT
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Which would assume (in these cold temps) there is something wrong with the coolant system...?
Why?

The thermostat decides on the engine temperature, therfore it should be the same regardless of ambient temperature. The only thing that changes is the length of time it takes to warm the engine up. Has your car actually overheated?
 

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TEAM 88 MOTORSPORT
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could do with another AGU owner to chip in really couldn't we mate! What made you check it with vag-com to pick up on the temp? If it were my diesel lump i wouldn't be concerned because I know they run above 90 deg
 

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Discussion Starter · #11 ·
yeah definately mate lol. but basing it on my old derv it ran spot on temp wise. I did logs a month ago which showed the temps at 96 when giving it a boot and 90ish when off the throttle. The question was raised yesterday when i had the car on a rolling road and bill (badger 5) noticed my coolant temp was high...
 

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Discussion Starter · #13 ·
always used g12++ recently replaced a couple of hoses due to a leak and i drained and refilled the expansion tank. Only had the car 6ish weeks and so far its cost me nearly half its value again lol! I need to contact the garage who did the cambelt to see if they have record of the pump. The belt was done about 20k ago. If its a standard pump then i assume it could be knackered (plastic impellor) etc..
 

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pauly4226
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had a n audi a4 with agu lump,never run above 90.i think cooling fans used to cut in at 92,off again at 84. audi a3 apu engine was the same.if the impellor has fallen off it will not pump at all,no matter what the revs.poss thermostat issue? although most of us know that you should change the water pump on cambelt change not every garage does.why not run it long enough for the cooling fans to kick in.
 

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Discussion Starter · #16 ·
thanks for your reply, u guess it may have been like this for a good couple of weeks... during that time ive done quite a few miles... long journeys/ town trips etc... its never got any hotter... was running on the dyno quite a bit... either idling or having runs (did 5-6 runs in total)... and it never got any hotter...

no codes or anything as such being picked up via VCDS... hmm
 

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Discussion Starter · #18 ·
Flow from the pump seems to be ok... Took the return hose off and watched it flow when reving at 4,000rpm and it poors out like a jet wash lol.

Ive been advised to change the thermostat and temp sensor (mainly the thermostat)...

At idle or below 3,000rpm the temp stays over 100 being driven or idling... as soon as i hit 4,000 or above the car cools down to 97.5 like clock work...
 
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