[Jeffreywp1]

My oil pressure light has been flickering after about 20 minutes of driving only at idle. After reading some info from another thread, I checked to see if my oil cooler was getting warm, and it was cool to the touch with the car warmed up and running. The oil pan was hot to the touch. Is the oil thermostat something that cleaning could help? eEuroparts sells just the spring, would that be all I need to replace or do I need the whole kit?

 

[Jeffreywp1]

eEuroparts sells just the spring, would that be all I need to replace or do I need the whole kit?

Answering my own question after reading how a thermostat works, I would need the whole kit.

 

[Jeffreywp1]

What would be the harm in running without an oil thermostat? I would assume none in the summer, but what about winter time?

 

[shaggy]

Oil not getting to Normal Operating Temperature (in winter). Increased wear would be one concern...

 

[Jeffreywp1]

How long does it take to get up to temp. I drove about ten minutes to the store, then straight back home with the air temp at 87 or so. Took about 15 minutes for me to change cloths and get the car up on ramps to check the oil cooler, which was cool to the touch.

 

[Jeffreywp1]

Would it be ok to run without the oil thermostat to see if it makes a difference during the summer time?

 

[Jeffreywp1]

Should the oil thermostat open up on a 20 minute drive in warm conditions?

 

[shaggy]

I’m afraid I can’t answer your questions regarding timing and temperatures but i’d suspect after 20 minutes the oil should be at or at least close to normal operating temperatures.
If you are getting a flickering oil pressure light you will definitely want to ensure that your sump is clean with no sludge or “coffee grinds” blocking your pick-up. If you have those problems then removing your thermostat would be a band-aid at best. However, if that is what you are going to try, then certainly summer would be the time of year to try it.
There are many threads on sump cleaning if you search...
Good luck
S

 

[Jeffreywp1]

I cleaned the sump almost three years ago and only use Mobil 1. Would like to hope that sludge is not and issue and would not like to go through the sump drop again. It is a real pain because my sump has the extra lip for the manual transmission that they did away with in later years. I do not believe my oil thermostat is opening up and my brand new oil is fairly dark looking already. I tried putting an endoscope in the sump when I changed the oil but could not get it turn up to see the screen. It is also like clock work that the oil light flickers. Either just as I get to work or just as I get home. I drove it this morning for the first time this week and the oil lines to the cooler where not warm. Will check that again when I get home.

 

[Jeffreywp1]

The local pick and pull had a 03 9-5 so I went and pulled the thermostat out and pulled the one out of my 01 and put them in a pot to bring to a boil. Both pins started out at 9mm extension. The one from the pick and pull started opening at 99c and reached 11.5mm extension and the one from my car never moved after boiling for a few minutes. I hope this makes a difference.

 

[hunterstein555]

The local pick and pull had a 03 9-5 so I went and pulled the thermostat out and pulled the one out of my 01 and put them in a pot to bring to a boil. Both pins started out at 9mm extension. The one from the pick and pull started opening at 99c and reached 11.5mm extension and the one from my car never moved after boiling for a few minutes. I hope this makes a difference.

That sounds like some promising results, and a good idea! I hope it helps

For what it's worth and not to scare you, if sludge was present, it does seem to follow the symptom of flickering the oil light after 20 minutes (or so) of driving, and at idle

 

[Jeffreywp1]

The light still flickered. I will change the oil one more time. When I first changed the oil from 5w 30 to 5w 40, the light did not flicker for a few days. Would the oil getting hot make it lose viscosity permanently?

 

[Jeffreywp1]

I changed the oil pressure switch and it seems to have been the issue. At least now I have a more responsive oil thermostat. ;ol;

 

[hunterstein555]

I'd probably recommend installing an oil pressure gauge just incase

You can get an adapter that goes right in between the block and the oil filter, and you port in the oil pressure sensor. Wire it up to the dashboard, and it looks nice. That way you know your oil pressure. Super easy to install. Maybe $100

Or, if you're confident, keep on driving!