It started out running fine after sitting overnight, until you shut it off and then restart it. Then you can't hardly keep it running. As long as you are driving, it stays running, but misses really bad. As soon as you push in the clutch it stalls. It started out intermittent, and would only do it once in a while. Now it has gotten a lot worse. The only things I've tried were the igniter, coil, and fuel filter. The plugs, wires, dist cap, and rotor button are relatively new. The pickup inside the distributor reads 180 ohms as advertised. Any advice/opinions would be greatly appreciated.

 

Is this a 22RE (fuel injection). If so check the following: vacuum lecks at pvc and egr system, air filter, timing and cold start injector. These are the check from my FSM for rough idle/stalling.Hope this helps

Nathan

 

Thanks for the reply, but no, unfortunately, it's not a 22RE. Tonight, we tried new plugs, plug wires, dist cap, rotor button, fuel filter again, and fuel pump. We also cleaned the carbon buildup from the EGR valve assy. We did a compression test, and all 4 cylinders had good compression. We also sprayed WD-40 all around the base of the carb and the intake manifold, but found no leaks. Right now, I'm pretty stumped. I'm thinking either the carb or the gas tank may have some junk in it, intermittently blocking the flow. That's the only logical conclusion I can come up with since it is still intermittent. I'm

 

vacume lines. mine was doing the same thing, until i found the vacume line that was loose. check all connections, and use propane to check the lines.

 

I use starting fiuld to find leaks, it seems to get in small leaks better than wd-40, a bit more flammable as well. Also clean/replace your air filter. If its not breathing well it will so up at idle.
FSM troubleshooting for carb: Idle speed incorrect (700 rpm), slow jet clogged, Idle mixture incorrect(3 1/2 turn out from fully seated) fuel cut solenoid valve not open, choke system, secondary thottle valve not closed.
Clean the carb. and check all the linkage.
The choke VCV(vacuum control valve) is in the middle of the the intake manifold with three vac lines, one to EGR and two go to choke plate. Do the 'butterfly' valves operate smoothly? How does it run w/o the air cleaner?
stop you'll never figure it out with brain damage

Nathan

1985 22R 4x4 pick up

 

Joez, how do you use propane to check the lines? (I'm not the most proficient mechanic--still learning the tricks).

growinseed, I will try the starting fluid. Also, I don't think that the carb is out of adjustment, because sometimes it sits there and purrs like a kitten. Then all of a sudden she just dies. No spitting/sputtering, nothing. Just like you turned off the key. Last night, searching the web, I found a lot of people talking about the AAP diaghram being busted. I wonder if that could cause what I am experiencing? Thanks for the replies!

 

Don't know if you found this but AAP is the auxiliary acceleration pump. Its on the head side of carb and held to carb body with three screws. Inside is a spring and a diaphragm. Its controlled by a single vacuum line. I'd check both connections on this before you pull it apart. From the name it sounds like a fuel pump for when you 'step on it'.
It sound like some kind of vac switch/line to me. Does it die near normal op. temp.? i.e. when a vac switch is changing.
I also have an old GMC presmog, simple carb. It had similar symtoms just needed a new air filter, at throttle it could pull enough air but idle no dice.
Good luck

Nathan

P.S. propane seems a bit scary to me, but with an unlit torch you can probably trace the lines with the engine running and if a leak pulls the propane in you'll hear a response in the idle. Same idea as WD or starting fuild.

 

yup, thats it, just crack the vavle on a torch (UNLIT!!!) and pass it over the vacume lines. i have used it to find leakes that wd missed. i have never had any problems with it, and dont worry, propane seemed scary to me at forst too.

 

It does the same thing whether the air cleaner is on or not. Everything seems to be working okay on the carb, and we lubed all the linkages. It does only do it once it warms up. When it's on fast idle, it's enough to keep it running. Once it kicks off fast idle, that's when the problems begin. Today, I drove it to work (about 7 miles) without a glitch. Ran like a top. I think that's what confuses me the most. It will run perfect up until the point it decides to throw a fit. And there doesn't seem to be any key thing or time that it's happening. It just does it at random. I'm learning a lot from this board though! Thanks!

 

Maybe all the fiddling and fixed it . Let us know. Try and pay attention to the situation IF it arises again. I don't know if ramdon events are true unless of course its an electrical short. i.e. grounding only during certain circumstances. That might be it and vacuum hose with a crack that only appears in specific situations. Just guessing here.
When this is over walk to the pub and get yourself a

Nathan

 

same problem exactly. haven't fixed it yet, but, mine needs new air filter and brake master cylinder as well as plugs are a bit old. checked all vacum hoses, none loose, appear to be in good shape. checked all wire connections, all are tight except the one off the positive side of the battery. think they may go to starter. was pointed in that direction while searching. also the idle solenoid on the back of the carb. unplug black wire and turn on ignition, then turn off ignition plug back in and turn ignition back on, it should make a clicking sound. also power valve on carb and rumor has it that there is a fuel filter inside the carb, just below the needle and seat. hope this points you in the right direction. just start simple and cheap when shooting in the dark.

 

Did anyone mention fuel filter?