My dad drove my F150 in today(cause I was fixing his brakes)and he found some problems.

1st. Engine runs crappily. Kept stalling out when he was driving and felt like it was dieing.

2nd. When I put new valvecovers on, I installed a K&N Oil breather. Oil was spewing out of the filter onto my block. I imagine that whatever is making my truck run like crap is causing my oil pressure to raise?

I normally do city driving, he was driving on the highway for a long time.

Also, I have the two gas tanks, I had a little gas in the one tank that sat for a long time, and I recently burned it all up. Could that be an issue?

1993 F150
5.0/302
E4OD Trans
Shortbed/regcab
2wd

 

yeah the old fuel would contribute to your drivabilty problems.

 

I am not using the old fuel anymore though.

I start using the old fuel for a few days, burn it up, switch to new tank, drive a little, next day this happens.

 

The old, nasty fuel didn't help. Change the fuel filter and run some injector cleaner. Check for codes, this thread explains how: https://www.f150forum.com/f10/how-retrieve-trouble-codes-obdi-10907/
The oil spewing from the breather is from blow-by, the piston rings are worn. You should do a compression check to see how bad they are.

 

Been there, check and make sure your exhaust system isn't plugged up anywhere.

 

Don't let Dad drive your truck anymore !!! LOL