A4 1.9 PD TDI 130 losing coolant

[Jacko1]

Hello ,

A4 1.9 PD TDI 130 losing coolant , no obvious external leaks from hoses etc , no mayo in the oil -
strange additional symptom is that internal cabin vents red hot on passenger side and cold on driver side when calling for cabin cooling.

Possibly a blockage somewhere ? water pump failure ? should I start with a sniff test ?

Anyone have any ideas?

 

[Asahi]

Hello ,

A4 1.9 PD TDI 130 loosing coolant , no obvious external leaks from hoses etc , no mayo in the oil -
strange additional symptom is that internal cabin vents red hot on passenger side and cold on driver side when calling for cabin cooling.

Possibly a blockage somewhere ? water pump failure ? should I start with a sniff test ?

Anyone have any ideas?

Have you checked the flange at the rear of the engine? I was losing coolant at one point and it turned out to have a hairline crack in it as it's plastic

 

[AudiSporter]

Flange can warp over time with heat cycles. Plenty on ebay. So it's worth inspecting it just in case.

 

[Bhavick]

Hello ,

A4 1.9 PD TDI 130 loosing coolant , no obvious external leaks from hoses etc , no mayo in the oil -
strange additional symptom is that internal cabin vents red hot on passenger side and cold on driver side when calling for cabin cooling.

Possibly a blockage somewhere ? water pump failure ? should I start with a sniff test ?

Anyone have any ideas?

I haven't got an Audi myself but I have got a VW Golf MK4 1.9 TDI PD100 and I recently had a coolant leak. After purchasing a coolant pressure tester and pressuring the coolant system the leak revealed itself pretty quickly. First it looked like it was coming from the temperature sensor but after changing that out it still continued to leak, it turns out it was coming from the coolant flange.

What happened in my case was a piece of the groove inside the flange had broken off where the o ring sits inside and that was causing coolant to leak out down on to the gearbox. If it does turn out to be your flange or sensor try and buy genuine Audi parts or at least OEM quality as in my case I settled for buying a cheaper flange off eBay and I had a horrendous time getting it to fit properly to the cylinder head no matter how hard I tightened the two 10mm fitting bolts. I think these cheaper flanges and sensors are not made to the same quality as genuine parts. In the end i had to contact darksidedevelopments and order a genuine VW coolant flange and Beru temperature sensor and since fitting both i haven't had a single leak since. Good luck mate i hope you get everything sorted. I hate when stuff goes wrong with cars thankfully there's forums like this that will hopefully save you some time and money.

Just to show you here is the cheap flange I brought off eBay: https://www.ebay.co.uk/itm/162994854109

Thanks

 

[Jacko1]

I haven't got an Audi myself but I have got a VW Golf MK4 1.9 TDI PD100 and I recently had a coolant leak. After purchasing a coolant pressure tester and pressuring the coolant system the leak revealed itself pretty quickly. First it looked like it was coming from the temperature sensor but after changing that out it still continued to leak, it turns out it was coming from the coolant flange.

What happened in my case was a piece of the groove inside the flange had broken off where the o ring sits inside and that was causing coolant to leak out down on to the gearbox. If it does turn out to be your flange or sensor try and buy genuine Audi parts or at least OEM quality as in my case I settled for buying a cheaper flange off eBay and I had a horrendous time getting it to fit properly to the cylinder head no matter how hard I tightened the two 10mm fitting bolts. I think these cheaper flanges and sensors are not made to the same quality as genuine parts. In the end i had to contact darksidedevelopments and order a genuine VW coolant flange and Beru temperature sensor and since fitting both i haven't had a single leak since. Good luck mate i hope you get everything sorted. I hate when stuff goes wrong with cars thankfully there's forums like this that will hopefully save you some time and money.

Just to show you here is the cheap flange I brought off eBay: https://www.ebay.co.uk/itm/162994854109

Thanks

Thanks for the reply Sir.
I did resolve the issue thankfully , it turned out to be the coolant reservoir cap was faulty and there was as a result an airlock in the coolant system. Changed the cap and then ran the engine with the cap off with the heater set to hot to purge the air out and its not lost any coolant since.