Just performed an oil change on my 93 V6 with Cast.for over 75k oil and FRAM filter and now during idle the oil pressure is mid range range however during driving it is almost max. oit (already checked oil weight and filtermodel).

 

Bad relief valve in filter. Put in something else besides Fram.

 

Thanks I'll try it. is FRAM known for this poor quality release valves?

 

pete have i ever told you your my HERO.

 

Thanks.I changed the oil filter (non-FRAM) and still during strat-up/cold both during driving and at idle the oil pressure is high (80) , however after a while the oil pressure at idle does drop to 40 (mid-range) however during driving it is still at 80.

Help ?

 

t

 

Could have sworn v6 gauges had 0-60-120 for the oil pressure gauge, and z28 has 0-40-80.

 

Mine's a 3.4L '93 woth a 0-80. Any ideas on the cause ?

 

You may want to verify that the pressure gage is working properly, by connecting a mechanical test gage in place of the oil pressure sending unit. The sending unit or the gage could have gone bad. Although it would be a strange coincidence that the went bad after you changed oil & filer. Also there is a possibility that the oil may have been mis-labeled, and that you have something much heavier grade than the 5W30 or 10W30 recommended.

 

Thanks and I'll try it. Do you knwo teh oil press. spec for a 3.4L during idle and driving ? Could a bad PCV cause this ?