carb problems.

[86taco]

My truck hessitates and spitts and sputters when cruising down the highway. Seems like it only does it when the motor is warmed up. It doesnt do it constantly, only every once in a while. I will have to let off the gas and ease back into is slowly and it wont do it again for a few minutes. The truck is a 84' toy hilux with a 22r and the carb is giving me fits. The truck sat for 8 years so I had to line the gas tand it was really rusty. I have cleaned the carb about 4 times. I have a new air filter, fuel filter, plugs, I have tried 2 different sets of plug wires, there are no vacuum leaks. Its driving me nuts. I wonder if its the coil, I need to test that. It starts great and runs fine other than this hiccup. Any ideas.

[speedy]

Mine is currently doing just that, but worse. Mine does it over 50 or under a load like if I am climbing a hill on the freeway. I have a weber 38, a factory mechanical fuel pump, and a brand new DUI ignition system. I am fairly certain it isn't the ignition since what I have is a major upgrade to factory and brand new. I opened up my carb and found little to no debris in it. I cut open the fuel filter and found a bunch of peeled off paint from the inside of the fuel tank. My fuel tank was leaking anytime I had more than half a tank of gas in it. I suspect that it is rusting above the halfway point in the tank and the debris is clogging up my fuel system. When I took the tank off I noticed the filter screen at the bottom of the gas pickup in the tank had fallen off and was sliding around inside the tank. I have replaced the fuel filter, blown out all the lines all the way to the carb, and I am expecting a brand new tank to show up at my front door tomorrow. Hopefully this fixes it for me. I will let you know when I have it all put back together hopefully by the end of the week.

[86taco]

Mine seems to do it at around 45 or 50. I even tried 2 different fuel pumps. Wish it was injected.

[speedy]

Yeah, I see a 302 fuel injected V-8 in mine soon. I just keep running into issues with the 22r, and I want to be able to pull a pop up camper.

[Sean]

Are you sure the choke isn't sticking on? Whats your mileage like? Extremely poor?

[speedy]

The new tank is hooked up. Initial drives today and last night seem to indicate everything is back to normal. I don't think it was paint from inside the tank that was clogging it up, I think now that it was inferior soft gas lines that had begun to degrade.

[86taco]

I get around 20 m.p.g. with the 22r 4 speed and 31's. I know it snot teh choke sticking on because its manual. Took the coil off to have one of my dads buddies check to see if its breaking down when it gets warm. Other than that I am clueless. I drove it again the other day and it started up fine and I got up to 55 and it started to cut out and when I mash on it when it is cutting out its like the power is dead, but if I let off of it and ease back into it its fine. Some times it just spitts and sputters like its missing a little. But you cant tell it at idle. It purrs like a kitten

[86taco]

The coil tested ok. Anyone have any ideas?? What other tests can i do to it to figure it out.

[dirtytrucker]

Glad I am not the only one with this problem. All Though I think I have it the worst. My truck jumps and spudders anytime i have it under load. I can Rev it up in Neutral no problem But IF i try to go anywhere its lIke riding a bucking bronc.It Does it cold (bad) and warm (not quite as bad) It does it up hill down hill. when ever it wants... basicly... Honestly This Being my first yota I checked the things I know in common to all trucks about Like Plugs/wires/cap/rotor. And fuel filter. But I will be honest I dont know crap about weber's I am taking it to the guy who does know today though.

[DeadlyPeace]

Did you replace the old rubber fuel lines?
How much NEW gas have you run through it so far?


Check the choke breaker diaphragm
1. Apply vacuum
2. Vacuum should not drop immediately
3. Choke valve should open slightly

Check choke opener diaphragm
1. Apply vacuum
2. Vacuum should not drop immediately
3. Linkage should move

Check the fuel shut off solenoid
1. Remove
2. Connect terminals to battery
3. You should be able to feel a click
4. Make sure that the o-ring stays in place. Sometimes they'll catch on the treads on the carb while installing them and push the o-ring out of place and causing a leak.

Double check that the choke is working right, both while it's cold and hot.

Re-check the fuel filters. I'd also sugguest putting two in-line filters in.


Could be your accelerator pump (carb) or the ignition module (distributor). Can't remember if there's a test you can do on these other then replacing them.

[86taco]

Thanks deadly I will check them out.

[speedy]

I'll officially say that my problem is solved. I replaced the gas tank, the fuel lines, and the fuel filter. I cleaned the jets in my carb although they didn't appear to be dirty. I think mine was getting it the worst at higher speeds and loads because it wasn't pumping enough fuel into the engine and it would begin to die when the fuel load wasn't keeping up with demand. Mine also idled perfectly when this was going on and I could not replicate the problem in the driveway by revving it. I probably could have solved my issue with a simple fuel filter replacement along with a couple of fuel lines. If your using a fuel filter similar to mine, it's super cheap, cut it open and look for debris to verify for good that that isn't the problem. Have you blown air thru the fuel lines yet? There could be a clog that is only a problem when the engine is demanding more fuel.

[86taco]

I dont think I have tried to blow air thru the lines, that could be a possibility. I use the clear plastic filters. I should change the fuel lines but havnt yet. MIght mess with it this weekend.