No oil pressure

[Hedgetrimmer]

My 4200 dropped to Zero oil pressure while idling today. There was no tell tale noise from the tappets and the rest of the engine sounded completely ok. At first I turned the car off and did some searching on the internet as I was about 2 miles from home. I concluded (possibly may regret it later) that the sender unit was at fault so drove home at low revs (not that that would make any difference!).

Anyone know how to replace the sender? I understand that it fits into the right cylinder bank but I cannot spot the part. I can see the part I need on the eurospares website and would prefer to change myself as the nearest indie is over 100 miles away.

 

[conaero]

The sender is situated on top of the block in the V at the back under the plenum.

It's a right pig to get to and you can either remove the plenum or lay on the plenum with your arm down the back of it cursing and swearing, the choice is yours.

Good luck!

 

[Hedgetrimmer]

Cheers Matt. I have now spotted the culpret. Hopefully it is just the sender as my oil pressure is now back up to 5 bar.

 

[safrane]

You can use a bent spanner to get it off without removing the phelem as long as the bolt is in the right position

 

[k99]

If the oil pressure is back to normal it might have been a dodgy?
Before you swap out the sensor and if it's safe to do - can you run the engine and get someone to watch the gauge whilst you check the wire or connector is not loose/intermittent. It might save you replacing the sensor only to find it was a dirty connector?
Keep your mits away from any hot or rotatating parts and take your tie off!!

 

[Emtee]

Cheers Matt. I have now spotted the culpret. Hopefully it is just the sender as my oil pressure is now back up to 5 bar.

Hi Hedgetrimmer, Is that 5 bar at warm idle or under throttle? Should read around 2.5 bar at warm idle. Have you noticed the oil pressure needle jumping around at all?

 

[Hedgetrimmer]

I spent some time cleaning up the connections on the sender today. The nut was pretty easy to undo so that may have been the issue. However, it was not possible to check whether cleaning up and tightening everything has made a difference as the oil pressure returned yesterday anyway.

I am tempted to give Marius a ring at Autoshield tomorrow. The car is due a service in the next couple of months and I might get the car recovered to him for an early service post checking that there is nothing wrong with oil pressure.

 

[Dave]

oil sender

I'm unsure about my sender, still getting some spurious readings..........I had a debate earlier on this year......if you do change the sender can you keep hold of the old one please. I'd like to identify it's true identity ie find a pattern equivalent and make up a crowsfoot spanner to fit. Brilliant if you could.....I'm happy to pay postage. Cheers

 

[javier]

I had a similar problem in my 3200GT. Oil pressure, from time to time, started wandering around sometimes (usually coincident with a road bump) and then back to normal in seconds, or minutes, or after another road dump , so I suspected the wiring. After messing around with the connector and cleaning it, it seemed to be back to normal during quite a long time - but one day started dropping worringly low but only when hot (after 30 minutes or 1 hour driving). It turned to be a sensor failure but only when heated - after replacing the sensor, all back to normal. Regards

 

[Hedgetrimmer]

I am pleased to say that Autoshield has now diagnosed the problem as being a dodgy sender unit only. A mechanical guage proved that the oil pressure was strong and all is back to normal after changing the unit. I got the car serviced at the same time and replaced the rear wishbones due to excessive play at the same time so didn't get off too lightly. It was a pleasure dealing with Marius who is a spot on guy.

 

[Parisien]

Good to hear HT....sigh of relief all around!

Agree...Marios...good guy to deal with.


P

 

[Emtee]

Sounds like a good outcome with minimal expense. Just wish Maserati could have designed a sender that wasn't so flaky in the first place, as this is a common problem. Good to hear a recommendation for Autoshield also.