Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Trending News

Promoted
Skipper
Skipper asked in Cars & TransportationCar MakesJeep · 7 years ago

97 jeep grand cherokee 4.0, oil pressure at idol is zero, but when rpms are1500 pressure goes up?

I recently rebuilt the 4.0, brand new oil pump, head gasket, oil pressure sending unit. Checked the piston ring pressure, and getting 150psi on each cylinder. What could it be, faulty oil pump?

Update:

Yes, new crank bearings, crank was ground down .020 rod and main caps brand new. New bearings everywhere.

2 Answers

Relevance
  • ?
    Lv 5
    7 years ago

    Bad oil pressure switches from the aftermarket have plauged the 4.0L for years. Also, many don't see that the 96-98 is different than other years. Highly recommend Omix-Ada replacement.

  • JES
    Lv 6
    7 years ago

    Did you put new bearings on the crankshaft? Rod and mains? That will do it.

Still have questions? Get your answers by asking now.