I would check the connections starting at the sending unit.
God Bless America, Bill O|||||||O
http://www.billhughes.com/

Ralph DL wrote:
>
> The oil pressure gauge on my TJ is high, 40+, while the engine runs at
> road speeds, but at idle the needle sometimes drops to zero, and then
> climbs up to about 10 pounds. Sometimes while at idle it swings back
> and forth between 0 and 10.
>
> I disconnected the electric oil pressure sending unit and attached a
> mechanical gauge... same behavior... the pressure falls and rises at
> idle like before.
>
> The Jeep is a 1997 TJ 4 cylinder, with 71,000 miles.
>
> Apparently I need a new oil pump. But I wonder if the oil pump might be
> good and something else is causing the deviance.
>
> Is the pump driven by the distributer shaft?... could the pump be good
> and something else is causing the oil pressure to sometimes drop and
> rise like that?
>
> The Jeep runs well and behaves normally at idle or road speeds.
>
> I change oil and filter every 3,000 miles.
>
> TIA for your advice.
>
> Ralph
>
>
> God exists, or God does not exist, or I am God and I am dreaming all
> this.