240 oil light problem

[old_MrSmith_and_his_Volvo]

Bit of an odd problem, has anyone else had this one?

I just bought an 1987 240 sedan, GL, just shy of 400,000k's
the oil light intermittently comes on and off, it seems to go off and on if you go over a bit of a bump in the road, will ether switch the light on and off, sometimes stays on for awhile, then will go off for awhile.

Maybe some sort of electrical problem? or a more serious problem with the oil pump itself?

The car doesn't have an oil pressure gauge, so unfortunately no clues to be gained there.

Car is full of oil and only leaking a small drop overnight, normal for old Volvos I think to leak from somewhere or everywhere.

car is a non-turbo.


Car is not running hot at all, drives fine, no lack of power or engine noise problems.



Would appreciate any ideas, thanks.

 

[johfraser]

The oil pressure sensor is next to the oil filter. If the sensor wire gets damaged and connects to ground it turns on the light. The wire runs under the front crank pulley, then to the firewall and through it to the light. It may go through a large connector on the firewall as well.

It is unusual for the sensors to fail but may be damaged or broken since it is near the oil filter and alternator.

 

[old_MrSmith_and_his_Volvo]

interesting, thanks, I was reading in the service history about some repairs to the alternator bracket.
I will have a dig about, thanks for your help

 

[old_MrSmith_and_his_Volvo]

johfraser; FYI, found the problem today, bare wiring touching against the alternator

thanks for your help.

 

[johfraser]

Congrats! It might be worth observing if the insulation was worn through by vibration or is crumbling. If the later, it may also be happening inside the sheathing under the crank pulley. Some year models have an insulation problem generally. Check near any connectors on the firewall too.