mikedog

I finally have my 22r running pretty well. Good throttle response, crisp performance and decent fuel economy. However, I believe I may have a choke problem when warming up.

1-2 presses on the gas pedal and the truck starts up nice and quick at 1200-1500 rpm fast idle speed. After warming up to operating temp, it then kicks down to a nice and smooth 700-750 rpm.

However, it's exactly at this transition point between cold fast idle and normal warm idle speed that it will stumble for a few seconds almost ready to stall before settling back to 700-750 rpms. This only seems to happen on cold engine starts only.

I've rebuilt the original carb by myself, but I didn't alter or change any of the settings on the carb. I realize you can adjust the stock electric choke by replacing the rivits with screws and grinding down the "nub" on the housing to make it adjustable. However, what would cause the choke to become "misadjusted" over the years to cause these kinds of symptoms?

I do have a 160* thermostat in it though. Unfortunately, it seems to do the same thing with the stock 195* stat as well.

Do you think maybe the BVSV sensor might have something to do with this problem? I previously had a "port" break off on me and I had to superglue it back on a long time ago.

HaveBlue

Why do you have a 160° thermostat in there? There's no benefit to having a cooler thermo in a carbed engine. Just thought I'd point that out.

My '83 does something similar. I can let it sit and idle up to normal operating temperature while scraping ice or snow off. As soon as it is up to the right temp, it idles down. However, mine does not stall or anything until I start driving. If I come up to a stop light and the temp gauge is at 1/8-1/4, the engine dies. Don't know what it is either. I rebuilt my carb, too. Flushed my cooling system and replaced the thermo with a 195°. Otherwise, engine runs like a top.

mikedog

Hey HaveBlue,

Thanks for the reply. Yeah, my engine kinda wants to stall for a few seconds after warm kick-down to normal idle speed. However, it doesn't actually stall out on me or anything. It goes down to about 400-500 rpms for a few seconds before going back up to the normal 700-750 rpms idle speed.

Your problem sounds like the EGR valve to me. Did you clean out all the tubes ports etc to the EGR valve? They get packed up with a lot of carbon, gunk etc.

Running a cooler stat on my engine has really benefited me. During the 100*+ summer months, my engine would experience significant heat soak when driving around in city traffic. With the stock 195* stat, the throttle response and performance would get real "mushy" in hot weather. With the 160* stat, the throttle response and performance was always crisp and very responsive no matter how hot the outside temps got. However, I may need to go to a slightly warmer stat considering that the temps are a lot cooler now.LOL!

mikedog

Anybody else have this same problem with their 22r? If so, what did you do to fix it?

Am I going to have to make the stock electric choke "adjustable" to cure this problem?

Thanks.

Al Paca

Don't mean to revive a dead thread but it sounds like the issue wasn't resolved and I too have the same problem with my 81 22r 4x4 (stock). Fires right up usually with cold starts, idles good at 2000 while warming up, reaches op temp and kicks back down to about 900... 10 seconds go by and it stumbles and tries to stall, sometimes it does stall... then it bounces back up to 900 and is fine. The only time it didn't do this is when I put a Weber on it which leads me to think it's emissions/vacuum related. Went from 20+ mpg to 14 mpg with the Weber so I rebuilt to stock carb and the problem returned.

Any thoughts?

Kilo392k

Yes I have the same problem here.

2ToyGuy

There's a nice write up in the FSM for your truck on how to adjust the automatic choke linkages. That complex looking set of screws and so forth on the passenger side of the carb. If you need, I can try to find, and post, the right page(s) here for you.
Make sure the BVSV on the front of the engine, the one with two vacuum lines, is functioning correctly. Heck, make sure all the sensors like that are functioning correctly. Same for the VSV's.

Check the vacuum lines against the sticker under the hood, to ensure they're not leaking, and all go where they should. As many as there are, it's easy for two to get swapped by accident. Worth a look.
If your sticker isn't there, or isn't readable, just do a Google, or whatever, search for you trucks year + vacuum line sticker. They're out there. You can download a jpg to carry with you, and several places have the stickers for sale. Good information to have when you need it. I have a number of pics of stickers for various years, models, and emissions set ups.

Also, once it kicks down off high idle, I always give the gas pedal a kick, to ensure the choke is opened completely. It sticks once in a while, and won't idle correctly. Same as described. If you want, you can pull the top off the air cleaner and watch to see if the choke opens properly, and completely, when the high idle kicks down. If it starts sticking too often, I take some WD-40 and lube everything that moves in, on, and around the carb. I have to do that once every two years or so.

Good luck, and keep us informed!
Pat☺