Mechanic Diagnosis thus far: New Throttle Positioning Sensor (TPS) and a new Air Flow Meter (AFM)
Parts Price: $825
EIGHT BILLS!!!!! AHHHHHHHHHHHHH
Did you already pay for those? If not then ask to have them replaced with your parts because you really dont want to pay that much for those man! I just checked with
http://www.car-part.com, and both of those can be had for under $75 easily. You dont need a new Toyota unit, a junk yard replacement will do just fine, seriously. And if it doesnt, then get a 2nd one, heck used air flow meters are only like $30 - $40 anyways..
White smoke when the engine is cold is perfectly normal. Even if alot of water is dripping from the tail pipe, dont let this scare you. Now if its still puking out white under hard acceleration when warm, now you've got problems.
The "choke injector" (Cold Start Injector) won't really effect much as it is ONLY used during cranking. It is not used when the truck is warming up. So if it has a hard start or takes a while to start, then you might suspect this, but otherwise its not to blame. Most of the time its not going to be the cold start injector..
When you say rough idle, are you saying that its rough at idle speed, 800rpm? If so then yeah, do a compression check or your valves might be out of adjustment, like you've got a couple really really loose valves
If the idle is poor and its low or bounces around, then Air flow and tps is definitely where I would start. Also make sure that the ignitor is bolted down firmly and has a good ground.
Also, if you look at the air flow meter, some have this blocked off and some do not, there is a spot which looks like an adjustment screw. It's flat and just looks like its part of the aluminum housing, but actually there is a set screw about 3/4" down. Take a small drill and start drilling into it. You will break into a small cavity so be careful not to damage the set screw. Then use a larger drill, one just larger than a screw driver that you will use to change the set screw, and once you get it opened up, adjust it. BUt only a bit!
This is the air bypass for the air flow meter. The screw is covered because it is a set amount of bypass from the factory and they dont want any one messing with it. Also, this can really affect your chances at the smog station.
My MR2 failed but everything seemed fine, so Marlin showed me how do drill that "dummy flat spot" out and I gained access to the set screw. I turned it down a couple turns and the idle came up a bit, got alot smoother, and I passed smog the same day. I was using an air flow meter from an 85 MR2, which is box shaped, whereas my 87 is supposed to have a D shapped airflow meter. So the air flow was set for a 85 ECU, not my 87. So a simple screw solved my problem.
And some air flows have this screw visible already, there is nothing to drill out. So if you can see a set screw on your AFM, then mark where it is and then start playing with it. With your truck idling, start turning it. Try to turn it out 2 turns and see what happens. If the idle gets worse, then go down 2 turns (back to before) and then 2 turns again (now you are 2 turns down) and see how that does. Just go a ways up and compare that with a ways down from stock.
This is worth the time to try, so I hope it helps ya!
BigMike