Technical Low oil pressure - stop engine.

[Morty Mort]

Hello.

I know there are some posts about this issue on the forum, but I couldn't really find my solution.

Story: The car has had all faults, and after a FIAT tech. changed the ECU etc. under warranty the car has been very stable for nearly a year now.

Anyway, I've got a "low oil pressure - stop engine" warning light about 10 times since this summer. The car has been used nearly every day. This has happened only once those particular days, and always at the day's first start. Strangely most common when the car had been parked in the sun and there was hot???

If I stop the engine and restart it, the problem is gone. Another cure has been to give it a step on the throttle, as it idles at slightly less RPM (very little). Just after this throttle push, the idle is ok and the fault signal dissappears. The fault has never arrived when driving - that would make me scared.

I have never tried to drive off with this warning. There are no engine sounds that shouldn't be there. No tapping noises so far.

It uses almost no oil. The Uno and the Ritmo drank oil steadily as fuel, but this one is very greedy. Oil is checked regulary. The car is a 2002, 1.6 litre. No mods yet.

So what I'm thinking is:
- Faulty signal from the oil pressure sensor.
- Faulty sensor.
- Bad connection somewhere.
- Something's dirty at the intake, causing the lower idling, and then causing an actual low pressure.
- Worst: General low pressure.

But how and where to start. I've never dismantled or done anything on this car. The Uno was kind of simpler to break into pieces and rebuild - like Lego. I have no idea what to clean, what to remove, or where the oil pressure sensor is etc. This ended as a long story, but I took the car to Fiat today to make them check it, and he was sure he would use at least 4 hours, maybe more. Maybe it included two lunch breaks and a shag at the backroom with the female sales woman, but 4 hours + to plug a computer or check the oil pressure was a bit too much. So I need your opinion first. One hour labor at Fiat costs £ 75 GBP, and I really can't afford it if nothing comes out of it...

Help!

Morten.

 

[SLOVAC]

Hi Morten,

This might sound silly, but usually when I get this warning it's because my oil level is slightly low. Like you I will get the warning on hot days or when I I've been driving the car hard around some twisty roads AND the oil level is slightly low.
Try it, check your oil level via the dipstick... all you might need is a quick pint... uhh, I mean, all the car might need is a quick pint of oil. Hope you get it sorted!

Cheers,
Slovac.

 

[Deckchair5]

I have exactly the same "fault" a the moment, same car as well. If it happens then it's always on the first start of the day and before the engine's even started. "Silly impatient boy, of course the oil pressure is low, the engine's not going yet"
Just like yours, it doesn't come on at any other time during the drive, if it did then I'd be seriously worried

It's not the oil level on this occasion as I'd checked that

My thoughts are
My battery is starting to shows signs of age - highly likely to trigger warnings on start up but would have expected the ASR warnings to happen too
Could do with an oil and filter change
I'll pull off and clean the electrical connector to the oil pressure switch, reconnect and see what happens

The next thiing I'd do is take out the oil pressure switch and plug an oil pressure gauge in and see just what the oil pressure is during normal running

After that I'd think about changing the switch, it's looks like a very normal oil pressure switch. It's usually located pretty close to the oil filter


Here it is, the large curved tube shown is the base of the oil filler tube so it's going to be accessed from underneath the car. Deep joy!

 

[PNL]

I haven't had his on my 1.6 at all [thank god] another case of are all these damn sensors necessary I have future plans to fit some gages on my car permanently because if driving and the oil light comes on then its already to late and the engine will have sustained some damage already its a more satisfactory situation with a gauge as you can monitor the situation better and not have to rely on those stupid damn sensors

 

[arti_abarth]

In my case 'low oil pressure' warning light really ment something - now my 2.4 engine's bottom end is beeing rebuilt. One of the couple half bearings was totally gone - all that was left was very thin metal ring - and due to this damage lots of oil pressure was lost. At first when the fault light came on I tried to explain it to myself as pressure sensor faulty - but I was VERY wrong.
So let somebody check it ASAP - becouse it may be too late!!! Also oil level in the engine was just under max mark and the light was flashing for split of a second when I was taking corners too quick.

 

[Deckchair5]

That's low oil pressure warning with the engine actually running. The grim reaper's calling card. The Abarth Ace of Spades

This is different, low oil pressure warning before the engine is even started. No warnings with engine running

 

[activematt]

Mine used to give me this warning time to time on start up during the check, but would always say ok afterwards. Like others have said it only seemed to do it when it was either a warm day or if id start the car up after it had been running, so still warm. Personally i just ignored it after checking levels and stuff

 

[johns]

I think you need to get the pressure checked (if you don't have a gauge - I only know that the abarths do have an electronic gauge), as it could be an early sign of another problem, such as the shells are worn on the crank. If the engine is off ignore the warning, but if it is on it could well be an early warning that you should take head of


IIf the oil pressure is generally ok and it is diagnosed as nothing major, before you waste your money on a sensor try a higher viscosity oil. The higher the viscosity the more difficult it is to flow and so the more pressure it generates (and tends to hold pressure better on idle). Try Mobil 1 15w50 - I've found it holds higher pressure better especially when hot

 

[Gaz Lear]

i had that problem as well, but the reason i had it was i had no oil in the car :bang: whacked some in and jobs a good un, no warning light since

 

[Argonought]

If the oil pressure is generally ok and it is diagnosed as nothing major, before you waste your money on a sensor try a higher viscosity oil. The higher the viscosity the more difficult it is to flow and so the more pressure it generates (and tends to hold pressure better on idle). Try Mobil 1 15w50 - I've found it holds higher pressure better especially when hot

Could be some risks involved in going for a higher viscosity oil than the engine was designed for :chin:

Modern engines tend to be built to a very precise clearance with a move to really quite low viscosity oils such as 40 or even 30. If the oil can't get to the areas it's intended to get to then the wear rate could be quite high and the only clue you'd get would be slight power loss (too late by then )

Personally, I think buying a sensor could be a lot cheaper

 

[dropthepuck]

I used to get all sorts of messages. Oil pressure, high coolant temperature (it was 0 degrees outside and it was the first start!), air bag failure, this failure and that failure. The oil pressure one scared the heck out of me, but like you say it was always on the first start of the day. I had the dealer check it out and they said it was fine, but gave no suggestion what was wrong or what to do! One day the car would not start at all. RAC diagnosed a bad battery, so I bought a "better" replacement battery from Costco and haven't had a warning since.

I would suggest getting the dealer to look at it, but I think it has been mentioned on the board before, that the Fiat battery provided with the Stilo is just not strong enough for all the kit onboard and can cause these warning messages.

 

[Morty Mort]

Hello again. Thanks for many good replies. I am not really concerned about this, as the car has had all maintenance services at Fiat, and owned by an old man who propably never has gone over 3000 RPM. The engine (or wheels) has rolled 46.000 km (27.600 miles) and I doubt any bearings are worn. I will anyway have the whole thing ckecked at next service.

I think I will do an oil and filter change, check the oil pressure switch for dirt etc and clean it. If the message appears again, I will deliver the car to an independent workshop for pressure testing. They said it'd take under an hour, where Fiat needed at least four...

I've never been under the Stilo's engine before - anything I should check at the same time? Will I need to remove the undertray? Propably.

Morten.

 

[Deckchair5]

Well, whilst you're underneath, whip out and inspect the air filter as this isn't touched unless requested until 36k miles- way too long
I haven't had any more low oil pressure warnings so i'm assuming bad contact at the oil pressure switch for me perhaps

 

[Morty Mort]

Well, whilst you're underneath, whip out and inspect the air filter as this isn't touched unless requested until 36k miles- way too long.

Is that true? I changed filters on previous cars twice a year. One autumn, one spring. I'll pop it out and bang it clean. Waiting for Oldschool's filter to be available.

Morten.

 

[Deckchair5]

Put a new one in, they're not dear at around £10 from Halfords and do a reset, give your girl some air and let her breathe

 

[johns]

Could be some risks involved in going for a higher viscosity oil than the engine was designed for :chin:

Modern engines tend to be built to a very precise clearance with a move to really quite low viscosity oils such as 40 or even 30. If the oil can't get to the areas it's intended to get to then the wear rate could be quite high and the only clue you'd get would be slight power loss (too late by then )

Personally, I think buying a sensor could be a lot cheaper

Well the oil feed round the engine is exactly the same as the Coupe 20V Turbo and lots of owners use 15w/50. I have used it on my coupe for about 80k miles so no problem there. Fiat's recommended oil for the coupe is 10w60 Selenia. 15w/50 also allows you to use proper fully synthetic oils such as Motul.

 

[Argonought]

Well the oil feed round the engine is exactly the same as the Coupe 20V Turbo and lots of owners use 15w/50. I have used it on my coupe for about 80k miles so no problem there. Fiat's recommended oil for the coupe is 10w60 Selenia. 15w/50 also allows you to use proper fully synthetic oils such as Motul.

Like I said, if you use what the manufacturer recommends then it's not an issue. I certainly agree that fully synthetics are the way to go (assuming your motor's in top condition to start with)