:Ross Herbert wrote: : :> 20W-50 grade oil is NOT approved for the 307 petrol engines, particularly in :> Europe or wherever the weather gets very cold in Winter. Cold starting viscosity :> of 20W is far too high. :> :> The only approved oil grade for the 307 EW10A engine is 5W-40 synthetic with an :> ACEA A3/B4 rating (or better). There are plenty of brands which meet this spec. :> : :Thanks Ross, I was not aware of this and in fact at least two authorized :dealers have repetitively used 20W-50 on my car; call it negligence or :ignorance or whatever you like :-) : :However, I seriously doubt that 20W-50 is the cause of the "low pressure :warning" I get. If you know how I can have the car oil-pressure tested :myself and are willing to share some details, I would be much obliged. : :Nikos
I would change the oil first to the correct grade just in case the viscosity is preventing either the oil pressure sensor or the oil pump from producing the correct pressure.
I'm not a mechanic but I would think that if you do not have any oil leaks, there is no water in the oil (that is very easy to spot), the exhaust is not belching smoke,and you know that the oil level is correct (and it is the correct grade), then the only possible causes I can see are;
- Scored big-ends
- faulty oil pump
- faulty oil pressure switch (or sensor)
If you know that the engine is unlikely to have scored big-ends then I would be inclined to simply change the oil pressure switch first up - these do go faulty. On my other car the oil pressure lamp started to come up and I thought it couldn't be the pressure switch since I had put a new aftermarket one in only 2 years previously when the original sprung a leak. However, I decided that I would exchange it for a new genuine type and since then it has not come up in the last 12 months.