idle issues

[toyodaaddict]

ok my 84 22r (cal emissions) is giving me trouble it idles ruff and has a miss. problem #1 erratic idle, its set to idle at 850 but sometimes it will idle down to 500 or even 150 at which point it dies.it will act this way for maybe 15 minutes then pick back up and run around 850-1000. problem #2 the choke (electric) is kinda eratic also. and #3 the exhaust has a rumbling backfire when idling down hill and sometimes when down shifting.mainly I'm concerned about the idle but thought ide mention all the symptoms
   so far Ive checked the timing,looked for vacuum leaks,adjusted valves,changed plugs,wires,cap,roter,checked compression,changed egr valve(might not be getting vacuum?). I'm fairly new to this stuff and i need HELP.

[80_yota_pickup]

have you checked if each cylinder is getting spark? other then that sounds like it is something with the vacuum line.

[toyodaaddict]

have you checked if each cylinder is getting spark? other then that sounds like it is something with the vacuum line.

yes all cylinders are getting spark.i cant find any vacuum leeks.I'm really stuck

[Snowtoy]

From www.toyotanation.com/ on eratic idle

I hope you didn't order a new carb yet, read and do this and you might save some mula, it's worth the less than hour time to check and find out, mine did the same thing and this little AAP (Auxiliary Accelerator Pump) was the little bugger that caused my rough idle and soot on the spark plugs...

It might not be the choke at all, if it doesn't want to idle when you first start it cold, it might be the AAP diaphram.

Check on the side of the carb next to valve cover, there's a vacuum line that goes to a AAP valve (triangle shape) , which is a diaphram that is vacuum operated on the side of the carb.

Take off air cleaner and you'll see on vac line going to it. Pull the line and stick a BB or golf tee in line. Replace air cleaner and start truck if it's does go back to normal idle then that is the problem and get a new one. If it still doesn't idle right then that is not your problem. But it is an easy way to rule it out and doesn't cost you anything...
Must be something else. Good luck...

The aap diaphram is available from NAPA for about $12 + tax.

Other discussions on the 22r carb 

Did you check for a vacuum leak, or just check the vacuum lines?
The backfire symptom could be from too much fuel leaking into the cyls., however if it is more of a chug when backing off the gas, it could be an exhaust leak, or from too large of exhaust piping and muffler.

I still think the carb is probably shot and in need of a rebuild.

[toyodaaddict]

From www.toyotanation.com/ on eratic idleOther discussions on the 22r carb 

Did you check for a vacuum leak, or just check the vacuum lines?
The backfire symptom could be from too much fuel leaking into the cyls., however if it is more of a chug when backing off the gas, it could be an exhaust leak, or from too large of exhaust piping and muffler.

I still think the carb is probably shot and in need of a rebuild.

thanks i will check the aap tomarow.the idle problom isnt just when cold its random.i did my best to check for vacuum leeks at the base of the carb and the intake but it was kinda hard i used propane and starter fluid and it didnt idle up as for the exhaust its stock upto the flowmaster and 2.5 inch tail pipe.

[muddawg]

for sure the AAP valve/diaphragm, but also, replace the idle solenoid O-ring.  Disconnect wiring to the solenoid so they don't break (they get brittle).  Remove solenoid and pull the O-ring off, if it's still there, if not, clean out the passage with carb spray.  Also, clean choke flap with carb spray, removing all black deposits. 

PS lube the o-ring before installing, it's tight.

Put everything back together and you might have to drill air/fuel mixture cap to get access to the adj screw.  If this doesn't work, you'll need to get a carb kit. However, I do have weber I'm not using. 

[muddawg]

From www.toyotanation.com/ on eratic idleOther discussions on the 22r carb 

Did you check for a vacuum leak, or just check the vacuum lines?
The backfire symptom could be from too much fuel leaking into the cyls., however if it is more of a chug when backing off the gas, it could be an exhaust leak, or from too large of exhaust piping and muffler.

I still think the carb is probably shot and in need of a rebuild.

Easy way to check for vacuum leaks, when running, spray carb cleaner around everything and if it idle's up or dies you have a leak. 

[80_yota_pickup]

well if you have the stock carb then cap all the vacuum lines off and just hook up the advance

[toyodaaddict]

i spent the weekend following the tests in the fsm. the aap is fine the idle fuel cut solenoid o ring was worn so i replaced it that fixed the backfire problem.the idle still likes to drop  and my choke/fast idle are still messed up im going to try again this weekend but im about ready to try and find some one that can wire up efi for me or just have my carb rebuilt

[Stiffer_22]

Was there ever a solution to your problem?