1.6 TDI VW - OVERHEATING HELP!!!!!!!!

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Sun 11 Mar 2018 14:56
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - Roy Brown

1.6 tdi on 105k miles. Used to overheat when doing a regen going up hill or on inclines, now its happening driving up hill or inclines at any time

  • Timing belt and water pump changed
  • Genuine Thermostat (yes its in correct also)
  • Genuine Coolant temp sensor
  • Genuine Coolant flange
  • Genuine Secondary water pump near sump area changed
  • DPF deleted and gutted out (told it could be blocked) EGR valve deleted from map and blanked off (still same symptoms after)
  • New coolant cap
  • Heater inside car is perfect
  • Fans are working (as they are usually on...)
  • No smoke or smell of burning coolant
  • Passed a pressure test
  • No leaks
  • Car is driving perfect just overheats up hill or under load.....

PLEASE HELP - Have had this car with numerous mechanics including a 'VAG Specialist' and no better

Edited by Roy Brown on 11/03/2018 at 14:59

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Sun 11 Mar 2018 15:50
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - elekie&a/c doctor
I would get the radiator flow tested.however to do this will mean removal from the car. Not easy on these.Also,how do you know it’s overheating?
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Sun 11 Mar 2018 16:57
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - RobJP

1.6 tdi on 105k miles. Used to overheat when doing a regen going up hill or on inclines, now its happening driving up hill or inclines at any time

  • DPF deleted and gutted out (told it could be blocked) EGR valve deleted from map and blanked off (still same symptoms after)

Congratulations on failing your next MOT, where the DPF 'canister' part of the exhaust is checked, and if signs of interference are detected, then documentary evidence will be required for the repair/replacement or the DPF, or it will be an automatic 'major' fault, and thus a failure.

I wonder how expensive a new DPF is ... start saving !

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Sun 11 Mar 2018 17:32
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - Roy Brown

Ive looked up how to change the radiator, seems complicated as you say on these cars. I wouldnt go to that bother and not replace it....Temp guage and VCDS 110 degrees+

Edited by Roy Brown on 11/03/2018 at 17:33

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Sun 11 Mar 2018 17:35
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - Roy Brown

Congratulations on failing your next MOT, where the DPF 'canister' part of the exhaust is checked, and if signs of interference are detected, then documentary evidence will be required for the repair/replacement or the DPF, or it will be an automatic 'major' fault, and thus a failure.

I wonder how expensive a new DPF is ... start saving !

Thanks for your concern but not relevant to my problem on my original post...

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Sun 11 Mar 2018 19:26
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - bluezzr1100

Hi

The trouble with garages these days is that they cling to fault codes as a drowning man to a piece of floating debris.

Some obvious things to try would be airflow obstructions to the radiator-any mods that might have affected this or debris in the way.

It would be worth flushing the radiator in situ assuming that the hoses are accessible. Remove bottom and top hoses and pour water into the top-see what comes out and at what rate-this may just shift any obstructions. Better still contrive to introduce water into the lower end and see what comes out of the top. Repeat one way and the other until you see an improvement. I got my son's corsa heater rad unblocked by doing exactly this.

I cannot see taht it would be anything other than a partially blocked coolant circuit. Has anyone put sealant into the system at any time? Too much of this would cause problems!

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Sun 11 Mar 2018 21:24
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - Roy Brown

Hi

The trouble with garages these days is that they cling to fault codes as a drowning man to a piece of floating debris.

Some obvious things to try would be airflow obstructions to the radiator-any mods that might have affected this or debris in the way.

It would be worth flushing the radiator in situ assuming that the hoses are accessible. Remove bottom and top hoses and pour water into the top-see what comes out and at what rate-this may just shift any obstructions. Better still contrive to introduce water into the lower end and see what comes out of the top. Repeat one way and the other until you see an improvement. I got my son's corsa heater rad unblocked by doing exactly this.

I cannot see taht it would be anything other than a partially blocked coolant circuit. Has anyone put sealant into the system at any time? Too much of this would cause problems!

Hi, not sure about any sealant in the system, I know i havent added any. The car looked to have more water than coolant in the expansion bottle when I got it if thats any help?

I will try to flush the rad myself as I am desperate to get this sorted and dont think any of the garages actually flushed it, they just added new coolant everytime they changed something. I also ordered an infared thermometer in hope i could test it in situ.

A new one is only about £50 but it looks so awkward to fit and I've 'wasted' the guts of £500 trying to fix this :(

Edited by Roy Brown on 11/03/2018 at 21:32

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Wed 14 Mar 2018 18:14
1.6 TDI VW - OVERHEATING HELP!!!!!!!! - Lrac

If you get yourself a thermostat housing gasket first, you could remove the thermostat and replace the housing then take off the hose and put a garden hose into the housing and reverse flush the system after disconnecting the bottom hose first. I would expect to see what looks like sand flowing out. nearly forgot leave the heater turned on. good luck

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