Part identification

it's location is under throttle body it's an advanced distribution something it's sticking

 

only found on m/t. I think it's call a vacuum dash pot

 

@BartMaster1234

 

I'm AT what I've learned is that the EPA forced it on the last years truck was made. I cannot buy new one without having to buy entire throttle body. I used sensor cleaner in it and the mechanical push rod is freed up and comes out to the proper stopping point and truck idols fine until I hook back up to vacuum hose. The same vac hose that when disconnected would cause truck to run 1200rpm. Now with push rod working and vac hooked up truck stalls out. Complete opposite of what was happening when truck was first stalling.

 

My 02 v6 AT don't have it nor my AT v6 04. My 98 v6 MT T100 have it and my brother's 01 v6 MT.

 

That's why I'm having such a problem with it. Not many people are even aware this thing is there controlling my idle speed. When the push rod was stuck back I simply shimmed it with a nylon cap and drove the truck fine over to parts guy at Toyota to see first hand. He still didn't have a part # , this thing only comes on a new throttle housing that we could see in pic off his computer.

 

Its on 2.7 4 banger

 

You are right it is called vacuum dashpot. Vacuum throttle control. Plunger is what was stuck

 

No clue. Looks vacuum system related.

 

Its a dashpot.

 

A what now?

 

Throttle control vacuum. Toyota was made to put it on last year's of trucks production

 

Hope this help? @Boatbldr

On my 83 pickup swap 22rte 5 speed and other 22re engines, the dashpot didn't have a vacuum connection from the intake. Dashpot had a vacuum hose connected to it with a 1 way check valve and filter on the other end. Not sure if the tacoma designed is different from that.

If it serve the same purpose, vacuum might be leaking from the dashpot causing high idle since there's a connection from your intake to dashpot. Try capping off the vacuum hose from intake side and leave dashpot vent to atmosphere and see if it'll help. Worth a try.

See diagram



Even other toyota dashpot design don't use an intake vacuum to be connected

 

This Helps. I was actually considering doing something like this.

 

Thanks for the post and research

 

hope you're able to resolve your issue

 

I don't think it's a dashpot. A dashpot doesn't allow the throttle plate to suddenly snap shut when you let off the gas. It causes the throttle to take a second of two to completely close the last few millimeters.

I believe this might be the "throttle opener". When vacuum is applied to the diaphragm the pushrod is pulled in and it allows the throttle linkage to close completely. When no vacuum is applied the rod springs out and prevents the throttle from closing completely.

From the 1996 repair manual in the 4-cylinder section:
2. INSPECT THROTTLE VALVE
(a) Apply vacuum to the throttle opener.
(b) Check that there is no clearance between the throttle
stop screw and throttle lever when the closed throttle
position.

In any case, with the throttle completely closed the engine shouldn't be stalling because the IAC valve should be allowing air in and controlling the idle speed. It sounds like something else is wrong.

The diaphragm of the throttle opener should hold vacuum if you apply it with a hand vacuum pump. It may not be holding vacuum and that's a problem, but it sounds like you have another problem that is causing the stalling.

 

Push rod or plunger was stuck in.

 

What I'm seeing is metal to metal rubbing marks on tip of push rod or plunger its referred as. After 335000 miles I have fresh marks now that plunger is freed up and touching stop point on throttle. I'm concluding that I'm missing a sleeve over end of plunger.