1G 4G37 Rough idle, surging at speed

[Krawdad67]

I have a 93 Laser 1.8l n/t that was sitting for a while before I got it. It acts like it's cold natured, has a rough idle and surges and jerks when cruising at speed. It's not constant. and it only happens when running at a steady speed, going away when accelerating or decelerating.

Work so far includes new timing belt (no change), dropped fuel tank(found out that you can't buy an aftermarket tank) pressure washed the tank inside and out. Soaked 2 gallons of vinegar in the tank for 4 days, rotating after 2 days, followed by another round of pressure washing. Installed new fuel pump and pickup screen. Fuel gauge actually works when it's not caked with rust.

Also changed the fuel filter before filling it back up with fresh gas. I have ordered a new refurbished mass air flow sensor since spraying the mass air flow sensor with cleaner seemed to help for about 5 miles before it started the same issues. The only thing I can think to do while I wait for the new sensor is to recheck my timing. Forgot to add that there is no CEL

 

[dwb]

Check for vacuum leaks.

 

[Krawdad67]

Got new vacuum hoses and fired it up and sprayed starting fluid around intake manifold gaskets and the throttle body, no change in RPM