Hey,

Thought I'd post my findings in the search for my starting issue on my 88 22re. I found many references to surging idle, and rough warm idle, but not much at all related to my problem. The truck would take a start, but quickly die. You had to depress the gas pedal to get it to take and if you didn't get it going the first try, it would take a lot of effort to get to start. When it did start, the idle was very low, almost stalling low. Gradually as the vehicle warmed it went to normal idle (750 rpm). I couldn't really find anything referenced on the net that was similar so I hope this helps.

I went through the cold start system, but it was working fine (engine was flooding when starting). So I unplugged the hose from the Axillary Air Valve to the intake plenum and it started right up....then slowly died. Aha....After a bit of tear down, I have the AAV out and bingo....the bi-metal piece must be bad...cause it is closed at room temp. Being closed at cool temps, it wasn't allowing any air into the engine at start...causing the flooding problem. An engine need air, fuel, and spark. Air was missing.

Here is a pic of the inside of the AAV. See how the opening is blocked...at room temp this is not good. So about $250 in parts due next week and I'll report back.

 

I hope this fixes your problem. I don't know enough about this system to make any solid statements, but if that component is supposed to act as a 'choke' for cold starting, it should be blocking off some of the air.

A cold engine needs air/fuel ratios of 10:1 or higher for starting. Carbureted motors use a choke plate, that blocks off all but a small amount of air to achieve this air/fuel ratio. They can also use an enrichening system, which instead of limiting air adds a lot of fuel.

I believe our motors might use a combination of both of these. I know there is a cold start injector (the enrichener), and I am wondering if this is supposed to limit air supply at start up?

I really don't know, I'm just sayin. I do hope that $250 worth of parts takes care of your problem.

 

Here are the two pages from the FSM regarding the AAV.

They show that it is supposed to be open at low temp and closed at OT.
The on engine check of pinching produced no results either...so I am certain that this part at least is malfunctioning.

$250 was for the new OEM AAV and a bunch of gaskets. The AAV from Autozone, Duralast brand was $240. I figured for the same price I might as well go genuine.

I also went through most of the other items that could be causing issues, cold start time switch, temp sensor, cold start injector, AFM, Air temp sensor. Cleaning the throttle body really well helped slightly and I did find a break in the AC idle up vacuum line. But neither fixed the problem. I know I have good spark and timing and valve clearance (recently done). Plus the engine runs great after warming up. No power loss and good response on throttle. So if this isnt the solution...i'm fresh out of ideas. But we shall see.

I don't know much about carburetor engines as I have never owned one.

 

Ok, cool. Sounds like you're on it. Good work and I can't wait to hear of your results.

 

Well, I am very happy to report that the AAV was indeed the problem. Got it all back together this evening and she fired right up, hit fast idle speed and slowly came down to O/T idle speed. Needless to say, I am giddy with joy

 

Awesome! Good work, and good reporting!

 

Tucson native! Glad to see it worked out and that you actually reported back! Thankss

 

After a month of trying different things what fixed mine was putting new pickup in distributor and making sure gap was set around .015 thou

 

Raising this thread for the dead. I know the AAV is discontinued... anyone know where I could source one? (I don't have enough posts for a WTB yet)

 

You don't have any info in your profile, so hard to say where you are, but I am pretty certain that Yota Jim's in Denver would have em, and likely ship at your expense. I don't know of any aftermarket suppliers.

 

I found this thread helpful in diagnosing the issue we currently have with our 22re AAV. I have the same issue as mentioned previously. 1988 22re AAV is discontinued. I thought I found one online. It has the correct picture of the AAV but they sent me the IACV that bolts under the throttle body so I’m back to square one. Does A) anyone know where I can find one? (I’m assuming all the new OEM parts are gone. B) Is there another year or model that could work and can still be purchased new? It’s a common part on motors but a lot of the other types I’ve seen do not have the coolant by pass ports. C) Can these be rebuilt? Can the bimetal parts be replaced.

 

The bi metal heater use to be available separately from both Toyota and aftermarket years ago but it may be discontinued now.