2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly

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Fri 31 Jan 2020 13:18
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - Lee Beare

Hi

I've just replaced both coolant temperature sensors, one in the side of the engine and the other in the bottom hose, and the cooling fan, Mine is the one with just the one large fan.

I still have the same fault, which is, the fan comes on randomly. It will come on from cold and stay on a while. Sometimes I can do a few miles without it coming on at all. But mainly its on. Obviously when the fan is on the revs will tick over above 1000rpm. That's how I know the fan is running and when I switch off the engine it usually runs for a few seconds and sounds like a jet engine. I've got air con on this model and am aware that the fan will spin faster with this on but air con is not on when the fault occurs. I'm really stuck as to what it could be.

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Fri 31 Jan 2020 14:04
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - elekie&a/c doctor
I’m assuming no dpf on this car . The cooling fan has no direct connection to the temperature switches . The fan will operate according to parameters met by the engine control unit . You need to look at the live data from the engine Ecu to establish what is triggering the fan circuit. It could even be a wiring fault or an issue with the Aircon pressure switch.
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Fri 31 Jan 2020 17:06
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - Lee Beare

Thanks. Ill try the air con switch next. I dont have anyway of getting data from the ecu apart from paying a garage to check.

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Fri 31 Jan 2020 14:06
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - Railroad.

A 2008 model will be just before it became a legal requirement for all diesels to have a DPF, but yours may still have one as many did before they were required to. The cooling fan will run all the time the DPF is regenerating, and stay running for a while after the engine has been switched off. And since your car is now 12 years old it's quite likely that the DPF is fairly well blocked to the point where it regenerates regularly. You may soon need to replace it.

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Fri 31 Jan 2020 15:08
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - Lee Beare

A 2008 model will be just before it became a legal requirement for all diesels to have a DPF, but yours may still have one as many did before they were required to. The cooling fan will run all the time the DPF is regenerating, and stay running for a while after the engine has been switched off. And since your car is now 12 years old it's quite likely that the DPF is fairly well blocked to the point where it regenerates regularly. You may soon need to replace it.

just been speaking to VW. Gave my reg and they say no DPF fitted on my car.

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Fri 31 Jan 2020 21:10
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - medview

Suggest you switch off the airconditioner and the fan will probably stop running apart from when engine cooling is really needed, which is infrequently in winter.

Joe

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Sat 1 Feb 2020 09:42
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - Lee Beare

Air con isnt on

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Sun 16 Feb 2020 17:03
2008 VW Golf 1.9 tdi with BXE engine - cooling fan runs randomly - Lee Beare

Cleaned all the earth points in engine bay today.

Fault still there.

Need someone local who can scan for faults

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