Another question for my 89 f 150
 

Drive for about 20 minutes then the check engine light comes on. Park it and it smells like burnt oil or something. Next morning it's off again.

Suspect something with the EGR circuit, but recommend to pull the computer codes to see what it doesn't like - saves time AND money.

Challenge these days is that while many auto parts stores offer to read the codes at no cost, they may not have the reader for this vintage, as the readers for wayback were somewhat specific to the manufacturer. If so, may have to find a garage having this older style reader, scrounge around on the wide world of web to buy your own unit, or follow the directions to DIY using a paper clip.

The DIY instructions are found in the Sticky Notes section of the 87-96 subforum of this site - 1987 - 1996 F150 - Ford F150 Forum - Community of Ford Truck Fans.

As far as the burning smell, not sure whether related to the Check Engine light, may be just a valve cover gasket leaking or such.

FWIW, suggest your future posts would be better suited being placed in that forum - lots of knowledgeable guys more likely to see your queries and to help out.

I understand. In a nutshell, if your check engine light comes on after 20 minutes of driving and you smell burnt oil, it could be due to various issues, including oil leaks, overheating, exhaust problems, engine misfire, transmission issues, sensor malfunctions, or electrical problems

In a situation like that I start with cleaning the engine bay thoroughly then watch for oil leaks - 34 year old egr valve could be ready for replacement for sure

You could go to a self service car wash and spray everything off to begin with just be careful of the distributor and the alternator...

Good luck with it