VW Golf 1.6 tdi - Cold radiator hoses and overheating??????????

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Mon 7 May 2018 22:49
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

My radiator hoses are cold after driving and fans run on as the car overheats

No fault codes. No warning lights

Diagnostics measuring matches the temp guage overhating (120 degress) But driving wasy around town this never goes ove the 90 marks

Coolant temp sensor, thermostat, water pump an secondary water pump all replaced at separate times and the bled air out properly each time.

Whenever I open the expansion bottle cap after driving, big whoosh noise and coolant trickles out

The coolant level never drops in the car, when the hot cabin air is switched on it is very consistent until turned off, no drop of MPG

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Mon 7 May 2018 22:50
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

I also tried to flush radiator a few weeks ago, nothing apparent came out and seemed to be a consistent flow from both ends. But I suppose this is going to be different once the car is under pressure???

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Tue 8 May 2018 00:21
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Andrew-T

Whenever I open the expansion bottle cap after driving, big whoosh noise and coolant trickles out

So your cooling system is pressurising? Is that just the normal slight increase with warming up, or a serious overpressure?

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Tue 8 May 2018 16:03
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - kiss (keep it simple)

Water pump? Or head gasket leaking causing pressure which stops circulation.

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Tue 8 May 2018 20:09
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

Yes

Its worse when its overheating

Drive around town and opening expanision tank seems normal

Waterump changed as per 1st post

Edited by Roy Brown on 08/05/2018 at 20:09

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Tue 8 May 2018 23:34
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - elekie&a/c doctor

Have you had a block test done for combustion leakage into coolant system?

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Wed 9 May 2018 00:12
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Andrew-T

Drive around town and opening expanision tank seems normal

Diesels take several miles driving to warm up fully. Sounds to me as if the head gasket may be suspect, tho I hope not. Get the overflow tank tested for exhaust gases, as advised.

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Wed 9 May 2018 12:34
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - dieselnut

VW fitted a new type water pump in EA211 engines from obout 2013 I think.

This may be your problem.

It has an electrically operated sleeve in the pump that reduces coolant flow until the ECU decides to open it.

This sleeve sometimes sticks so the engine overheats.

I think if you take it to VW they should change the pump to a modified one, hopefully FOC.

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Wed 9 May 2018 22:12
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

VW fitted a new type water pump in EA211 engines from obout 2013 I think.

This may be your problem.

It has an electrically operated sleeve in the pump that reduces coolant flow until the ECU decides to open it.

This sleeve sometimes sticks so the engine overheats.

I think if you take it to VW they should change the pump to a modified one, hopefully FOC.

Is this the one near the sump? As I changed that one and the main water pump as stated in the 1st post but neither made any difference.

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Wed 9 May 2018 22:13
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

I have ordered a dye test to check the block, but surely if it was my headgasket it would have went by now? Its been like this since November!

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Wed 9 May 2018 22:27
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - elekie&a/c doctor

If there is evidence of combustion gases in the coolant,it may not be head gasket problems. More likely to be a failed Egr cooler/heat exchanger.

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Fri 11 May 2018 12:37
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

..

Edited by Roy Brown on 11/05/2018 at 12:42

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Thu 10 May 2018 12:02
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - dieselnut

" Is this the one near the sump? As I changed that one and the main water pump as stated in the 1st post but neither made any difference. "

It is the main pump driven by the cambelt.

As it is now controlled by the ECU it could just be a sensor fault.

If the ECU is being given incorrect info from a faulty sensor, it could be stopping the pump from circulating.

You could do with a diagnostic scan to see what is going on temperature wise.

Was the replacement pump a modified one. ( I don't know if there is a visual difference but obviously would be a different part No.)

Maybee check with VW.

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Fri 11 May 2018 12:43
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

The coolant does not drop at all Ive been driving it all week (300+ miles) and put a mark at the level which hasnt dropped.

The only evidence of combustion gases (I think) is the fact that after driving there seems to be pressure from the expansion tank when opening it which is more than usual. It overflows wonce opened but again, there is not excessive bubbles or any contamination in the bottle.

Can the egr cooler be 'on its way out' and may have been sealed up or a split in it etc?

Both waterpumps have been changed in the car, the main was done whenevr I bought it almost a year ago and was told it may be faulty so I changed it again but no difference.Sensor was changed also

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Sat 12 May 2018 17:20
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

Right, today I used a combustion tester. Started the car from cold and followed the instructions for the fluid. Let the car warm up and used the tester but the fluid remained the same colour.

So I went for a drive up hill until it overheating, drove easy back home, opened the tank cap slowiy, lots of coolant rushing out of there and steam (pressure)

Then used my tester, the fluid in it went from blue to yellowish green which is a ssign for combustion gases present.

No my question is how likely is it too be the EGR Cooler? The car is running 100% otherwise, averages 60 MPG, cabin heat is consistent with no drop outs, please help!

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Sat 12 May 2018 21:06
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - elekie&a/c doctor

The egr valve/cooler heat exchanger is more likely to be the cause of the problem than the head gasket. The cooler becomes porous and allows exhaust gas to enter the cooling system.

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Tue 15 May 2018 00:48
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown
Yes I would like to think you are correct, the car has only got 105k which is average for its age and seems to be well maintained over 9 years. If the head gasket was bad or the head was cracked surely it would have got a lot worse over those 6/7 months?

I did get the car remapped to remove the working of the egr and also blanked it off as it was very slow to drive and fault codes showed EGR. However the cooler is still part of the circuit, do you have any ideas how I can bypass this properly once and for all?
I know I can get a delete pipe for it but would really want to avoid that as it’s so much work to do anything Egr related on these engines!
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Sat 2 Jun 2018 22:08
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

Deleted the cooler today and made no difference!

After driving the top radiator hose has pressure in it but is cold........

But when I let it idle to it hits the 90 mark the top rad hose is warm?

HELP

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Tue 5 Jun 2018 23:16
VW Golf 1.6 tdi - Cold radiator hoses and overheating?????????? - Roy Brown

up

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