1981 yota

my 81 kinda had the same issue i never got it to 35 but if i got on the gas it would just drop idle and finally kick back up it did that till i put a new weber carb and took all the emissions crap from cali

1981 yota

and i cut my cat but once your in cali you probibly cant do that

drew303

Maybe drop the cat and run it straight piped (to see if it symptons change)... cat could be clogged?

Subzero2cirb

its not the cat or muffler, cat is brand new and its a highflow one and the muffler is a magnaflow . I have those vacuum lines on my air cleaner, but dont make a difference if i pull em off or not they still pull air in whether there on the air cleaner or not. also i know theres not a potato in the exhuast, cuz its a problem thats been getting progressively worse over the past couple of months and i took all exhaust off besides the manifold but it still bogged down. however i have found a vacuum valve that has begun to go out i can here it click repeatedly and every time it does i get a backfire, but i still dont think thats my major problem, probly just caused by it. oh and now when the throttle cuts out unless i keep it in gear and down rev it just stalls out. Very weird though it only stalls out when theres load on it, like i can rev it up and down like crazy when its in neutral but as soon as load gets on it, it tries to bog out and then it just cuts out.

Subzero2cirb

well i took off the exhaust and boy did she sound like a beast, but symptoms are the same, still just cuts out and dies. im gonna get a computer from pick n pull here tomorrow or the day after. if that aint it, im gonna have a toyota mechanic look at it, a real one not one that just throws parts at it, ya kno Not like a dealership, Adurr?

gotbetlog

Subzero did you ever get your truck running proper? I just purchased a 78 celica gt (~50000mi) with the same issue of not being able to go faster than 35 miles per hour. I have tried the solenoid fix, gas cap, checked for vacuum leaks and that didn't improve anything. I just bought the car and on the way back from the smog check it started acting up.

AND to all the yotatech's: you guys give some sound advice thanks!

Subzero2cirb

Haha yea i sure did , turns out it was the silliest thing. after replacing tons of parts i finally paid a guy who works at the dealership to take a look at it. Apparently the autozone and Napa fuel filters are different, the in&out tubes/ports are opposite. so thinking oh yeah ill go with the napa filter, it turned out i had switched the way the gas was flowing so it wasnt getting enough fuel. So i would try switching the lines going to the fuel filter theres only 2 ports so wouldnt hurt to try. also if you got $5 extra bucks just run to vautozone and get a new one so you dont suck dirt into your engine, you may just have a clogged fuel filter. Good luck hoped it helps. if not send another Q i have tons of possible solutions.

truckman1966

It's overfueling because the float fell off the arm

INFINITY

glad to hear that. sounds like the jokers at autozone grabbed the wrong one off of the shelf for you. the ones that i have bought from there have always worked great.

gotbetlog

I've been using Kragen generic filters. I tried to switch the in/out hoses on a new filter but that made the problem worse so Kragen filters are right. I put the fuel lines back the way they were and still cutting out at 35mph.

I have yet to check the emissions computer, spark modulator, egr valve, pcv valve, coil, and carburetor internals.

But what I have done is dirven with the gas cap off, checked the fuel cut solenoid, changed fuel filters, changed sparkplugs, ignition wires, distb. cap, and rotor. The fuel pump was just changed by the previous owner.

I also noticed that the previous owner put a ziptie on the actuator that operates the choke to keep it wide open is this an issue?

BTW this is the first carburetated car i've worked on so I'm not jumping in to the carb just yet. Is it hard to rebuild/work on/tune a carb?

truckman1966

take the 6 screws off the top of your carb, pull out your float arm, solder the float back onto it and readjust float level

77FJ40_79PU

My truck was having a lot of the same symptoms with bucking and lose of power i found out it was the ignition moduel it wasnt getting enough amps because the alternator was bad.

Pick-rolla-Pick

LOL, you got the Bioshock Infinite version of a Toyota truck, complete with Bucking Bronco!

Sorry to reply to such an old thread, but I just had to say that I have had similar problems of stalling, bucking and lurching while driving, and not holding idle upon start up sometimes with my 82 Hilux.

Had carb rebuilt, didn't fix but IMO needed it anyway as plug residue was white instead of tan and the factory ones have plugs vs mixture screws.

Replaced alternator, didn't fix it but it had a cheap O'Reiley on it, so the Beck Arnley was a good upgrade. Searched for a Denso, but none would fit.

Replaced plugs & wires with NGK, cap and rotor with Wells Gold, and air filter with Fram. Didn't fix it but those parts were showing wear anyway.

Bought a Wix fuel filter today and am hoping I get results like you OP. Never knew a dirty fuel filter could cause such problems, but I'll find out tomorrow.

A lot of us get called over zealous or lazy for buying too many parts trial and error or going to mechs, but when you consider how long this thread went on with no one suggesting a simple fuel filter, it just shows that anything complex can be over thought, and anything simple can be overlooked.