Dpf pressure sensor

[aquacultureman]

Hi.

Can anyone tell me the part no. for a genuine Volvo S40 dpf pressure sensor? Have an 'Engine system service required' warning light on, and suspect this part, but do not know the part no.
Thanks in advance.

[iainmd]

You'd need to post more details of your car before anyone can oblige. Either VIN or Model, year, engine, transmission.

[IainG]

Hi

Originally Posted by aquacultureman

Hi.

Can anyone tell me the part no. for a genuine Volvo S40 dpf pressure sensor? Have an 'Engine system service required' warning light on, and suspect this part, but do not know the part no.
Thanks in advance.

Worth reading the codes first but for info:-
Just had issues on my V50 and it was one of the 2 flexible pipes going from the DPF to the sensor, worth checking

https://www.volvoforums.org.uk/showthread.php?t=320969

https://www.volvoforums.org.uk/showthread.php?t=321183

Iain

[aquacultureman]

Originally Posted by iainmd

You'd need to post more details of your car before anyone can oblige. Either VIN or Model, year, engine, transmission.

December 2009 2 Litre diesel S40 manual

[wynnj]

The part no for my C30 1.6D 2009 is 30757189, but as advised in other replies it's best to get the codes read before randomly plugging in a £90+ replacement part. I recently replaced mine with one of these https://www.ebay.co.uk/itm/165070887128 and it cured my ECM 2A40 DTC and at £16 it wasn't too much to risk if the DPF sensor wasn't the problem.
The consequence for me of this sensor failure was all 4 glow plugs subsequently burnt out so I'm going to buy another and carry it as a spare in case it fails again. They take 5 mins to change provided you've got a pair of pliers and the right size torx key.
If I find the £16 ones fail prematurely in future then I'll fork out for the Volvo/ford one.
If you want original you can also search for Ford 3M5A-5L200-AB. The original fitted to my car was marked FoMoCo.

[aquacultureman]

Originally Posted by wynnj

The part no for my C30 1.6D 2009 is 30757189, but as advised in other replies it's best to get the codes read before randomly plugging in a £90+ replacement part. I recently replaced mine with one of these https://www.ebay.co.uk/itm/165070887128 and it cured my ECM 2A40 DTC and at £16 it wasn't too much to risk if the DPF sensor wasn't the problem.
The consequence for me of this sensor failure was all 4 glow plugs subsequently burnt out so I'm going to buy another and carry it as a spare in case it fails again. They take 5 mins to change provided you've got a pair of pliers and the right size torx key.
If I find the £16 ones fail prematurely in future then I'll fork out for the Volvo/ford one.
If you want original you can also search for Ford 3M5A-5L200-AB. The original fitted to my car was marked FoMoCo.

Ended up fitting OEM dpf sensor (30757189) from Volvo. Car appears to be cured!

[Simmy]

Originally Posted by wynnj

The part no for my C30 1.6D 2009 is 30757189, but as advised in other replies it's best to get the codes read before randomly plugging in a £90+ replacement part. I recently replaced mine with one of these https://www.ebay.co.uk/itm/165070887128 and it cured my ECM 2A40 DTC and at £16 it wasn't too much to risk if the DPF sensor wasn't the problem.
The consequence for me of this sensor failure was all 4 glow plugs subsequently burnt out so I'm going to buy another and carry it as a spare in case it fails again. They take 5 mins to change provided you've got a pair of pliers and the right size torx key.
If I find the £16 ones fail prematurely in future then I'll fork out for the Volvo/ford one.
If you want original you can also search for Ford 3M5A-5L200-AB. The original fitted to my car was marked FoMoCo.

i had one of thoes first it lasted 2 weeks i ended up buying a genuine ford/ volvo one problem solved

[wynnj]

Originally Posted by Simmy

i had one of thoes first it lasted 2 weeks i ended up buying a genuine ford/ volvo one problem solved

Thanks for your reply. Did you try claiming under their "5 yr warranty"?
I bought the 'cheap' option initially as I wasn't entirely sure what was going on and £16 outlay was better than £90 to find out the fault wasn't with the sensor. I didn't have enough data on what pressure differences to expect between a clean and blocked filter to test it off the car. I've now bought a 2nd one which I'll carry in the car and swap over straight away if the fault recurrs and then order a volvo one. I don't want to risk burning out all four glow plugs again!
As I said in another thread (rant!) a very bad design that a simple, relatively inexpensive, sensor failure should lead to 4 blown glow plugs which could have lead to a very expensive repair if a glow plug broke in the head on removal.

[Simmy]

no i binned it i was so pi55d off with it. i doubt if the faulty sensor burned out your glow plugs. the sensor is just a vac switch which tell s the ecu to increase fuel operate glowplugs and the egr to increase exhaust temp to 600 deg which burns the soot build up to ash which is then blown out of the exhaust glow plugs fail in a different way they go open circuit and stop glowing

[wynnj]

Originally Posted by Simmy

no i binned it i was so pi55d off with it. i doubt if the faulty sensor burned out your glow plugs. the sensor is just a vac switch which tell s the ecu to increase fuel operate glowplugs and the egr to increase exhaust temp to 600 deg which burns the soot build up to ash which is then blown out of the exhaust glow plugs fail in a different way they go open circuit and stop glowing

My understanding is that the the sensor is a pressure (not vacuum) difference device that measures the difference in pressure between the upstream and downstream sides of the DPF, with the output varying between nominally zero volts to 5 volts max.
If the filter is clear, there's little difference in pressure, if the filter is blocked there's a large difference and so the ECU activates the Regen cycle which in this engine uses the Glow Plugs to help raise the temperature. However, if the sensor fails in a way in a way that the ECU thinks the filter is blocked it will keep regenerating and hence the glow plugs will be hot for extended periods. If the sensor fails in the zero or low difference state the regen cycle will never get activated and the DPF will gradually get blocked.
My car with only 40K miles went from no DTCs to all 4 glow plugs being open circuit in a very short time with just two DTCs, ECM 2A40 (blocked filter) and ECM 6620 (glow plug control).
After replacing the pressure sensor ECM 2A40 disappeared but was left with ECM 6620 until the glow plugs were replaced. I can't think of any other reason for all 4 glow plugs to go open circuit over such a very short interval of time, especially as they don't seem to aid much in starting the car. The car still started like a petrol engine with no delay even in sub zero temperatures with all 4 GPs open circuit.