oil pressure problem

[rlsmarty]

hi all - i'm new to the forum. I have an 88 grand am le with 103K miles. The oil pressure gage registers at 40 pp when the car is started. After driving it will drop below 20 when idling at stop lights. When excelerating it rises. When I check the oil it is clean and full. This seems to be happening more on really hot days. Any advice would be greatly appreciated.

[skibum1111]

what weight oil are you running?

[rlsmarty]

I'm running 10/30. BTW - it's a Quad 4.

Originally Posted by skibum1111

what weight oil are you running?

[GTP Dad]

I would say your problem lies in the fact that the clearances in the engine are getting greater as it wears. You can do a couple of things change the oil you use in the summer to a heavier weight like 20W50 or use an additive like STP or other oil conditioner that will increase the thickness of the oil. I would recommend the heavier oil, especially in the summer.

Although the oil pressure you are getting is obviously enough for the engine as it is right now due to the fact that it is not overheating or causing you any other trouble. If you really are troubled by the oil pressure you could replace the oil pump with a high pressure/high volume pump but it would be a waste of money.

[rlsmarty]

Thank you very, very much. I appreciate your advice and will let you know how it works out.

Originally Posted by GTP Dad

I would say your problem lies in the fact that the clearances in the engine are getting greater as it wears. You can do a couple of things change the oil you use in the summer to a heavier weight like 20W50 or use an additive like STP or other oil conditioner that will increase the thickness of the oil. I would recommend the heavier oil, especially in the summer.

Although the oil pressure you are getting is obviously enough for the engine as it is right now due to the fact that it is not overheating or causing you any other trouble. If you really are troubled by the oil pressure you could replace the oil pump with a high pressure/high volume pump but it would be a waste of money.

[skibum1111]

I agree with the oil weight, i run 20-50 synthetic in the summer and 5-30 synthetic in the winter, and i usually have around 60 psi on the highway, and around 40psi at idle. and I have 235000 miles on the car.