I have a 1989 5.8, pulled all smog stuff when I changed valve cover gaskets. It idled like crap before but even worse now. I've sprayed upper engine down with gas and Showes no sign of vacuum leaks. Any advise please

 

I've got a intake and holly and eldebrock carbs. So if this is too much trouble I just change it over. I have a bronco, mustang, and I might have a work truck that 351w carb

 

Have you checked for stored codes? You may them even if the CEL isn't on.

Idle quality can suffer from a dirty, sticking IAC valve. Then there is other sensors such as the IAT, TPS, MAP, ECT, and O2 sensor.

You can check codes for free with just a jumper wire and some patience. If you can decipher the codes, just take a video of the flashes, upload the video and members here can help you.

You can also order or buy at the auto parts store, the Eqqus Innova OBD1 code reader and makes it simple to diagnose.