Ok, those of you that have the 22R motor:

You know how when you start your truck in the morning and the idle automatically goes high until the motor warms up, then drops down to normal? Well, mine seems to be doing just the opposite - it starts out low idle, then when it warms up, goes to high idle for a minute or two worth of driving, then goes to normal. I've heard the 22R has an automatic choke that causes the normal high idle on cold start.

So, has anyone had this problem, and how do I go about fixing it?

I've also noticed that when I suddenly go to WOT, the motor bogs down bigtime...want to fix that too, and I know it's all in the carb, but where?

 

On the choke issue, are you pushing the acclerator pedal two times in before starting the engine? Thats how the choke works.

The WOT sounds like your engine is either running too lean or too rich.
Do you have blue smoke or black smoke?

 

Haven't noticed any smoke. I don't have a blown head gasket if that's where you're going.

As far as pushing the accelerator pedal before starting, if I do it only twice, it'll run for a second then die. Usually I have to pump it several times before I start it to keep it running.

 

So...does anyone have any other ideas?

 

i have a similar issue and would like to see what others have to say. i have to pump mine a bunch of times to start too, but onces running it runs good

 

If the choke is working properly, one WOT pmp is all it sould take. Multiple pumps will actually disengage the choke.

Toyota lists the high idle for a 22R at 2,600 RPM (crazy huh?). The AAP (Auxilary Accelerator Pump) is a vacuum operated device that is supposed to allow the carburetor to run efficiently before the engine has warmed up (the most sought after and failed at attempt of the 70's/80's for most auto makers). If the vacuum diaphragm for this ruptures (as 20+ year old rubber naturally will) it causes a "running rich" side effect.

The easiest and most efficient solution would be to rebuild the carburetor (which SHOULD come with the AAP diaphragm) and perform a basic engine tune up. Ignition, valves, emissions, fuel delivery (in that order).

The automatic choke, as well as all adjacent carburetor operating devices, rely heavily on the thermo-wax vacuum switching valves surrounding the carburetor. One of these valves is almost guaranteed to be bad and will effect choke and emissions operations.

If you download an FSM from the link in my signature, a "1985 Toyota Truck/4Runner" manual is available as a PDF format. The major difference I noticed between 84 and 85 was the addition of a second electric vacuum switching valve.

 

Nice! Thank you! Alright...so if I'm planning on doing performance upgrades anyway, I might as well just get a new carb if a rebuild is in order...

Wait...I found this: 22R Aisin Carb FAQ Maybe I should try this first before I get excited.

 

Wow... that is a BEAUTIFULLY constructed article. SO, just basically need to read up on teh different vacuum-operated devices and their respective vacuum valves that operate them

 

Incorrect.
Multiple pumps after the engine is running will disengage the choke.
I've always used 2 pumps, never at WOT, always at around 1/2 throttle.

 

Well, the article I linked in my last post would seem to explain why I'm bogging down at WOT, which also seems to be the reason my auto choke isn't working. I tried the 2 pumps only bit last night and still the same result - no immediate high idle and it dies within seconds, unless I pump it several times before starting.

I suppose the question is now, if one of those valves has failed, would I be better off just buying a new performance carb, or rebuilding the stock one - keeping in mind cost since I just simply don't have the time to do it myself?