Citroen C1 oil pressure Stop warning

[Matt_Nottm]

My girlfriend has just bought a 2016 C1 (with the wet belt) and had her dad check it over. He thought the belt looked in good condition using the measuring guage and just from a visual point of view, but still thought it was worth replacing the oil, which was pretty black after draining it out, replacing the oil filter and removing the sump to check for any potential debris from the belt.

The process was pretty straight forward - there was no sign of any debris in the sump so it was cleaned and replaced. We used Castrol Magnatec 5w30 C2 (B71 2290) after checking multiple sources for the correct engine oil. The only issue was that we were unable to find a stock gasket for the sump so instead he had to use a sealant.

After everything was replaced my girlfriend turned the engine over and the oil pressure and STOP warning light came on and stayed on.

Our question is could the oil pressure sensor have tripped out when the oil was drained and hasn't reset. Or have we done something else wrong?

[PaulC5]

This topic has the recommended oils but has not been updated for 2 years so may not be correct. You can find your engine code in the car VIN letters. viewtopic.php?t=75918 To get the latest oil spec I would visit a Citroen dealer service desk and ask for a printout of the service schedule which includes the spec. It will also contain the latest timing belt checks/replacement intervals. They should not charge for this, I was not when I got the latest for our 308 after the oil spec changed a couple of years ago.

I do not know where the oil pressure sensor is on your car but was its connector removed when the sump was removed - if so maybe it has not been put back.

[Rp0thejester]

I would be looking at sump pump that could be blocked, wet belts can't really be checked unless you take the engine apart, way more work than a timing belt!! If the the oil was that bad it could mean a previous belt has deteriorated and blocked it.

[Paul-R]

AFAICS the correct oil for all wet belt engines is now 5W30 but, most importantly, it should be FPW9.55535/03. B71 2290 is now deprecated for these engines.

viewtopic.php?p=861692#p861692 follow the link

[Matt_Nottm]

This topic has the recommended oils but has not been updated for 2 years so may not be correct. You can find your engine code in the car VIN letters. viewtopic.php?t=75918 To get the latest oil spec I would visit a Citroen dealer service desk and ask for a printout of the service schedule which includes the spec. It will also contain the latest timing belt checks/replacement intervals. They should not charge for this, I was not when I got the latest for our 308 after the oil spec changed a couple of years ago.

I do not know where the oil pressure sensor is on your car but was its connector removed when the sump was removed - if so maybe it has not been put back.

So decoding the VIN came up with EB2 as the engine code and the charts on that link show 5w30 B71 2290 as ok whilst FPW9.55535/03 isn't

AFAICS the correct oil for all wet belt engines is now 5W30 but, most importantly, it should be FPW9.55535/03. B71 2290 is now deprecated for these engines.

viewtopic.php?p=861692#p861692 follow the link

..... but if this is correct, then that info may now be out of date.

My Girlfriend gave the local Citroen dealer a call but wasn't able to get any info from them over the phone, so we'll have a drive down and request the service schedule in person instead

[PaulC5]

The service schedule is a one page sheet with the car VIN on it so specific to your car and includes the oil spec which from above appears to have been changed to FPW9.55535/03 5w30. It lists the service items against mileage and years. Do not let them give you their service check sheet they fill in when doing a service, this is not the same thing. This topic has an example of what they look like viewtopic.php?t=80582

When there you could order a sump gasket for when you next need to remove it.

[Paul-R]

... but if this is correct, then that info may now be out of date.

Yes, that's it exactly. The forum thread is dated November 2024 and the Stellantis Network Bulletin is dated 10th of February 2025. As I said FPW9.55535/03 is the new spec.