New Toyota owner here, I got an 85 4x4, 22r, 32 inch tires, 252,000 miles on it. my truck is hard to start most of the time without the help of a little shot of starting fluid until its warmed up good, then it will start up pretty decent on its own. but after its running if you try to give it more than 1/8th or quarter throttle it just sputters really bad and will not rev up at all, I may need to make a video to show exactly how its doing. then once its warm up good and I start driving it, the truck just has hardly no power at all except for the very lower rpms. anything past 1/2 throttle and if falls on its face it seems, even after its warmed up completely.

 

Stock carb?

 

yea it still has the stock carb. I was going to attempt a overhaul on the carb, had it off the motor and on my work bench and was ready to take it apart but I decided not to cause it looked like a little more to it than what I first thought, so I cleaned it real good and put it back on motor. I really didnt want to take a chance on messing up the carb then having to fork out 400$ for a new rebuilt one. the timing is spot on, I check it with a timing light and specs according to the manual I got. its got new plugs and wires also. and today I also sprayed carb cleaner all around the carb and intake and didnt find any leaks anywhere. and I forgot to mention when you try to rev up the motor and starts its sputtering issue it will backfire through the carb.

 

Check timing?

 

sounds like possibly a fuel delivery issue or timing, is the float bowl half full (you can see thru the lil window on the front to the carb)

clogged fuel filter maybe or bad fuel pump.

for what its worth, after i overhauled my truck, i had serious fuel delivery problems which caused all the symptons you described minus the backfiring...

turned out the nipple off the original fuel filter (which were metal then) had broken off in the line and finally rusted n collapsed on itself blocking the line.

at that mileage tho, carb might just need to be rebuilt. Mines up there at 250k but my other 2wd had to be rebuilt awhile back around 200.

 

timing is good, new plugs and wires, replaced the fuel filter today but didnt change anything.

I drove the truck to work yesterday about 30 miles 1 way (5 are on the interstate). the truck didnt even have enough power to get over 60mph, I think I hit 65 once going down hill on the interstate. it idles perfect all day, starts up good, alot better than it used to. But when you try to give it anything past half throttle it just falls flat- no acceleration or feel like its actually pulling. Wide open it feels like its starving for fuel? it felt so embarrasing driving home last night when it took forever to get to 55 mph from a red light or stop sign . im guessing it just has to be carb related, I dont think a vacuum line would make it run this poorly from half to wide open throttle....would it?

 

mine had similar problems and the cam gear was off a tooth..

 

Just a little update....My brother helped me take the carb apart and we cleaned everything and used all new parts from the rebuild kit. it helped alot with the starting problem and it revs alot smoother.......but it still doesnt rev out completely and have any topend power. we also pulled the valve cover and it has not jumped time on the cam chain, its all good according to the manual. I also checked compression on the motor and all the cylinders read 195psi with the gas wide open. But all the spark plugs look kinda funny, half the electrode is white and the other half is very light black. ive put maybe 100 miles on it since I put new sparg plugs in. It lookes like its really lean maybe, and this may also go along with how it runs like its starving for fuel when you open it up.

 

sounds like the vacuum advance on your distributor is bad.

 

I second that.

Also check the electric idle cut solenoid too (the barrel shaped solenoid the screws into the carb closest to the firewall). If this fails, it doesn't open the internal vacuum circuit in the carb to let vacuum through to the advancer.
You can just hook a 12 volt (+ a ground) to the 2 wires that come out of it. You should hear a good healthy "click" from it when you apply voltage.

Use a hand vacuum pump and make sure BOTH diaphragms on the advancer hold vacuum and actually move the plate inside the distributor (I've been seeing TONS of bad ones lately), while you have the dist. cap off, also check and make sure the mechanical advance is working too (they can stick and cause a "no advance" situation). Try turning the rotor by hand and make sure it moves (and returns) smoothly. It should move about 10 degrees or so by hand, just make sure it feels smooth.

Keep us posted

 

Man I feel like such a dumb ass......all that my problem was I had my timing WAY off. I guess back when I said I used a timing light to set the timing, I must not have done it right. I drove the truck to work and let a guy that knows alot about these trucks drive it, and he said that acts like a timing problem, and said that he doesnt trust timing lights at all and always plays it by ear and how it runs. So I start adjusting the distributor and it starts acting so much better. I think I got it set pretty damn close. Now Im over in the far left lane on the interstate

I appreciate all the replies and help

 

I use a timing light on mine and don't have any issues, and I use a Harbor Freight timing light. My cam timing is slightly off due to a shaved block as well. Anything more then 3* advanced, mine runs like crap, it likes being right at 0* with the vacuum advance off the dizzy.

I have seen however instead of blaming the timing light, there is a possibility the harmonic balancer has failed in that it's a "two-piece" unit. If it slips at all, en the timing mark on it is no good. This would lead to a failure to properly time by timing light, since the mark is off.