rough running and have tried tons, can't figure it out

[bdbaker]

i am having trouble. i have a fj60 that is running rough at mid idle, it idles fine and runs fine when its on the floor. when i hold it steady at mid throttle it revs up then back down. i have tried tons, the cruiser has had a complete tune up, it has a new rebuilt carb, i have adjusted the timing, and the fuel pump and filter are fine. all vacuum hoses on the carb are fine,

the only thing i can think is that maybe there are some vacuum hoses on the smog pump that could cause this, the smog pump has been removed, but was wondering if some of the vacuum hoses that are connected to the smog pump could cause this???

please help cause i am out of solutions

 

[hank14]

Can you post pictures of your engine bay? That might help us see what's where it's supposed to be- or not.

Is the EGR valve hooked up? Have you tried bypassing it?

Who removed the smog pump, and what else was removed in the process. Check out some of the desmog threads (look in the FAQ thread at the top of the 60 board).

 

[krzyabncanuck]

If it is at about 1400 - 1800 rpm and then dropping and comming back up to 1400 - 1800 then it might be your Decel Fuel cut Vacuum switch.

 

[bdbaker]

found a broken piece in front of the carb, it screws down into the manifold and has 3 vacuum hoses attached to the top, going to replace this and see if there are any changes.

 

[hank14]

found a broken piece in front of the carb, it screws down into the manifold and has 3 vacuum hoses attached to the top, going to replace this and see if there are any changes.

That would be what the emissions manual calls the "gas filter."