white0311

Just got a 87 yota 22r 5 speed. The problem is it seems to be miss firing about half throttle and full throttle has no power, and sputters loudly.

JonnyBoy

Have you determined for sure it's a fuel or air issue? Is the rest of the "tune up" parts(spark plugs, plug wires, cap & rotor) still in good condition? Was the Weber installed by the previous owner, or did you just install it and this condition started?
We'd have just as much luck diagnosing the problem if you'd simply posted a picture of the rig and said "it doesn't run right, what's wrong with it?" Need more info to help you out.

white0311

Previous owner installed the carb, spark plugs, wires, rotor, cap button are new. And the fuel pressure regulator is set at four psi

JonnyBoy

Well, fuel pressure is a little high, recommended is 3.5 psi max, but it doesn't sound like that's the issue. I think I would check for vacuum leaks, particularly around the base of the carb and the gaskets in the adapter plate to the manifold. Unless the previous owner installed a different adapter, the ones that come with the Weber conversion kits are kind of problematic. Next to check would be the shaft that goes through the carb and holds the throttle plates. The holes through the throttle body there can get a little wallowed out and leak air as well, but that's usually after years of use. If no vacuum leaks in those places or anywhere else, I'd say you need to rebuild the carb or rejet it.

Another thought, with the fuel pressure regulator on there, did you leave the fuel return line that goes from the pump to the tank? Had a similar condition with a Weber install on a Dodge D50/Mitsu Mighty Max, and when we blocked off the fuel return line it went away and was no longer starving the carb. It's free to try, at least.

Oldscooltoys

could be a clogged jet or a vacuum line that needs to be plugged is it a after market carb or the stock? if it is after market then it could be u havent plugged one of the stock vacuum lines or the carb isnt put on right and could be getting air sucked in a spot that shouldnt be....my guess

87yo_ta

Here's an install guide that explains the basic install, tuning and troubleshooting. I had a 32/36 Weber for about 6 months then replaced it with a Weber 38. I LOVE my Weber! It's worth the little extra effort it takes to tune it correctly. Need help? Call Redline Weber and ask for Bud @ 1-800-733-2277 option #3. VERY nice guy and an expert on Webers, IMHO.