Hi, I have an 1981 SR5 4x4 with the 22R all stock(CA truck=emissions bonanza) . I've sank almost $1500 into what seems to be a fuel delivery issue and have not fixed the problem.

Cold starts(as long as not below freezing) are fine. Two pumps of the gas, choke sets, fires right up and high idle kicks in as it's supposed to. It get's near op temp and the choke lets off, high idle comes down to about 1100-1200rpm... about 10-15 seconds goes by and then it sputters, rpms drop and it dies unless I give it throttle which then smooths it out and it idles fine at 1000rpm. If it does die, it starts back up fine and idles good. It does this after every time the choke engages. The only time it hasn't done this is when i put a Weber 32/36 on it for a few months.

Now, on warm starts it would sometimes not want to idle after sitting for an hour or so. It turned over fine and when I let off the throttle it would just die. The only way to keep it going would be to stay on the throttle, it would miss and sound like an airplane but would eventually smooth out and idle fine.

Then, it would start missing and jerking(flooding? Could smell rich exhaust) as I drove down the highway. And then it would fix it's self. Then it would start up with this crap again as I decelerated and if I let the rpms drop it would die.

Took it to the only mechanic in town who did not want to touch a CA carbed truck so I put a Weber on it. He said the Aisin was flooding a lot because when he took it off there was fuel coming out of the vac lines. The Weber fixed the problem but it was always fussy on angles and I could not get it to run right. My mileage went from 20-23 to 13-16 so I had my carb rebuilt by Re-Carb Co. Yodaman here in Santa Rosa put it on and all is well... until now.

It still does the sputtering-wanting-to-die thing after the choke disengages. And as soon as I got up to 2000ft elevation or more, it wouldn't idle. The rpms would slowly drop over 30 sec or so and it would die. Trying to go up a steepish hill, it just flooded real bad and stalled. I could hear gurgling in the carb and vapor coming out when I took the air filter off. Back on level ground I could see the float level would just keep rising until it filled the sight glass and stalled the truck. I lowered the float level, fuel level sat at middle of the sight glass and it improved the idle a little. I advanced the timing and it seems to have helped smooth it out at 1000rpm. Idles OK now but...

Occasionally on warm starts after it's been sitting a couple of hours, I have to crank it quite a while, 10 seconds or so before it reluctantly starts with a cloud of white smoke bellowing from the tail pipe. Then the idle drops way down to 500rpms and runs real rough(at sea level again). I turn it off, start it back up and sometimes it idles fine again, sometimes it doesn't.

And now it's starting to do it's jerking/missing/bucking thing as I try to accelerate after decelerating or come down a long hill at 3000rpms.
I've checked around for vac leaks, can't find any.
EGR works fine.
Has a small leak right before the CAT
Carb cleaner on the ex manifold stalls the truck... not sure what that's about.
Did find a little sediment in the float bowl after only 400 miles on the rebuilt carb. Could sediment be clogging the jets???

There isn't any real consistency except for after the choke lets off. I'm ready to pull my hair out. Anyone have any insight?? I love this truck but...



It has:
new plugs
new distributor(cap, rotor the whole thing)
rebuilt original carb
new fuel filter


Any thoughts???

 

Ground your fuel cutoff solenoid and see if that helps. I had a similar problem, and I tracked it back to the computer box under the drivers side dash (gray box). I bypassed that by grounding the solenoid, and now my problem is gone. It's not a permanent fix, but something to try.

 

2000PRE, thanks I'll look into that. I feel like I have more than one issue going on seeing as one problem is consistent and the other isn't.

 

Well it started stalling on me again as I came home last night. Seems to have a bit of a power loss as well. As I decelerate for a bit or come around a corner it'll start jerking and when I press the clutch and let the rpms drop, it stalls. Starts right back up and won't stay started unless I feather the gas for a while then it'll idle fine again.

Just pulled out the fuel cut solenoid and it clicks every time I put power to it. So I guess that's not it.

Any other ideas? Ignition coil maybe? It kind of sounds electrical to me.

 

What's your fuel pressure? Running a mechanical pump? With or without spacer? Do you have a fuel pressure regulator?

Webers do fine on the street as high as 4-5 psi, offroad 1.5-2.5 is the ticket to deal with angles. I'm not very experienced with stock carbs specifically.

 

81 22R 34 years Check the Emission control computer, located on the left cabin wall , under the dash. Had jerking /bucking /missing problem at highway speed I would wiggle the white serial plug and the problem would go away, but the frequency of wiggling the plug caused me to take the box out, and open it up to find, it smelt of burnt electrical components. Replaced the box problem solved. When changing spark plugs for smog test noticed cracking on the cap for the main coil wire, pulled it apart, residue and the wire was little stuck replaced the coil and #4 wire with some Yansi wires I had, and a new ND cap & rotor. It passed pretest and failed low idle H/C at star station, said could be wires, bought new ND set today. In 2013 during rebuilt carb install, the brass J-K-L coolant temp switching valve for cold start vacuum,the plastic top broke off with the hose, so I jumped J and K and plugged the carb port. 2013 test passed 152 out of 152 Have another J-K-L valve and will restore that system. On the carb install, they had to adjust the throttle plate angle. Vacuum hoses look good on top, check underneath. What next the air in the tires? Hope this is helpful, Nothing compares to a good running toy motor. Looking for a mechanic in the Long Beach, Lakewood Calif. area experienced with 22R 220,000 and 20R 184,000 valve job, and possible block rebuilding, vacuum systems. I like to turn a wrench and enjoy working on the toy. Thanks Charles

 

Kinda sounds like a leaking AAP diphram. Pulling excessive fuel into the intake.

Valve lash too tight..?

Choke system faulty..?

Sticky carburetor linkages..?

Exhaust system restrictions..?

Debris in fuel system, sediment from fuel tank..?

Fuel filter/fuel pickup screen clogged..?

EGR system faulty/clogged EGR passages...?

 

Thank you for the post I received E mail notification, Yes Now that you mention the AAP that is most likely the problem. The carb was rebuilt two years ago, why not put a new one in now, planning to pull EGR, I run OEM, not easy to find now a days. Thanks Charles

 

Well, as far as the periodic stalling at idle problem goes, I decided to splice in a ground wire in between the carb and the four-prong harness directly to the neg terminal on the battery. I made it all the way up to Washington(for work) and that issue hasn't popped up again. It does diesel just a little bit though. With the ignition on(not running though), I was testing the connection of the fuel cut solenoid between the emissions computer box and harness but couldn't get my test light to shine... So I hard wired the ground.

Do still have some problems with the idle fluctuating sometimes though. At slight angles or at elevation, the idle sometimes drops from 1100rpm to 500rpm then reluctantly stalls over the course of a few minutes. But one pump of the gas brings it back up.

AAP looks good, I pulled off the vac line and no fuel came out.

EGR does it's job... Stalls the engine when I apply vacuum.

There is debris in the fuel system but not too much.

Next I will look at the valves. Cold starts start fine but the engine struggles after 10 seconds until it blows out what ever is in there and gets close to op temp. I'm considering more seriously now a 22RE swap by the end of the year. Although I might desmog and put the Weber back on in the mean time. I want to stay OEM but I agree that 34 years and all the excessive CA smog equipment are giving me a headache.

 

Check your vsv that connects your vac lines from the charcoal canister to your tvsv. See if it is opening when voltage is applied to it. Air from the charcoal canister is taken into consideration in regards to a/f mixture.