Oil pressure 1990 350 TBI

[TC90V1500]

I recently bought a 1990 1500 4x4 with 190k miles but well maintained inside and out with zippo rust. The oil pressure gauge was replaced since it was darting between 30 and over pegged at highway speed. Now it shows 30-40 at highway speed and around town but while waiting at a light for a few minutes it will drop to 10-15. It will also get the feeling of a miss or s stumble while sitting at a light for a few minutes.

This does not happen with the trans in park warming up.

Any suggestions what to look for. I hope she is not getting ready to bite the dust.

Thanks for any advise.

 

[zora]

you need to rent an oil pressure gauge and determine what the true oil pressure is. The sender may be giving you false readings or you have an issue. The rule of thumb is 10 psi per 1,000 rpm, so 4,000 rpm 40 psi.