OVERHEAT AND OIL PRESSURE

Raulpereg

Junior Member
Messages
71
Hi. Last weekend, at 32°C I decided to do some mountain roads with the GS. I was using during some time 2nd and 3rd gears pushing over 6K rpm. In same road but not so hot outside I saw the temperature go well over 90° (about 115 if I remember correctly), but this time I had the overheat light on so I had to stop, at that moment also the oil pressure went down and oil light started to flash intermittently. I checked the oil and coolant and they were at the correct level, in fact oil was over the max mark but I checked with the engine off and I think in this car has to be done on and idle, not sure. Is this normal? Did I push too much for the weather or could I have something to review? It was just a few minutes so I dont think this should be too much for that engine...Please, could you comment?
 

FIFTY

Member
Messages
3,100
Nope not normal I drove my 4200 up mt Vesuvius in similar heat and while it seemed hot the temp didn't budge past 90c

It is very likely that your fan relay is broken causing the fans to be stuck on the lower speed or not coming on at all. You can take the relay off and divert it so that the fan is stuck on the higher speed until you get a new part... It is a cheap part and easy to buy/replace

I would suggest considering a cooling system refresh new thermostat temp sensor and radiator especially if it is all the factory original parts. I found a cheaper alternative radiator at autodoc.
 

Raulpereg

Junior Member
Messages
71
Thanks! I have seen in the instructions that there are 2 relays for electronic cooling fan, called first and second speed. Which one do say to remove? First speed and then is stuck in the second? I wil check if both are ok
 

Zep

Moderator
Messages
9,110
Check both.

There is a fairly strong possibility it could be something other than the fans as you were driving at the time it got too hot.

It could be the thermostat, blocked radiator, kinked hose.
 

jmora

New Member
Messages
8
I had similar issue with mine few weeks ago, though the engine temp didnt go that high and the issue was a bad wiring of the 02 sensors causing electric issue and the engine oil pressure to drop at idle.
And I was driving at 45-50 degrees C
 

Raulpereg

Junior Member
Messages
71
I checked fuses and relays of both speeds and they are ok, so thats not the issue. Tomorrow I will continue investigating
 

mjheathcote

Centenary Club
Messages
9,033
The only time temp goes much over 90 is when stationary. The fans generally cut in around 98 and then pull the temp down. That's temp measured by the obd2 port.
My BMW M140i doesn't have a temp gauge but I use an old smartphone running the torque app constantly. Nearly had kittens first time running the app, the water temp runs at 112 degree C! Quick Google and this is the normal running temp for the B58 engine. Phew!
 

Lusso916

Junior Member
Messages
78
What is the oil pressure on tick over on a warm 3200, reason I'm asking on my 3200 that was written of by a bus on Fathers day it always read 50, looked at one at the weekend and the needle dropped to about 40 then back up on revs.
 

alfatwo

Member
Messages
5,517
What is the oil pressure on tick over on a warm 3200, reason I'm asking on my 3200 that was written of by a bus on Fathers day it always read 50, looked at one at the weekend and the needle dropped to about 40 then back up on revs.
Mine never drops below 5 bar hot or cold

It usually worn big end bearings that cause the oil pressure to drop on tick over

Dave
 

philw696

Member
Messages
25,120
Sad but true about worn big end bearings but the Maserati oil pressure sender unit is notoriously a poor quality device to be fair.
Make sure the oil/water pump is in good order too as it does a lot of work on the dry sump engines and I have first hand experience too.
 

Raulpereg

Junior Member
Messages
71
Hey, just to confirm that finally the overheat problem with my GS was the thermostat not opening correctly, so I have installed a new one at the official dealer. Not tested still be me though...hopefully this weekend!