Taking the Throttle Body Apart - Lower half.

[DOCTORBILL]

Since I have taken the TB upper half off and messed with it, I am
wondering if the TB lower half should be examined.

I notice from the Revered and venerated, holy Chilton Manual,
page 5-9, that there is an Air Control Valve (ACV) inside the TB Lower
Half at the rear of the device.

Engine Coolant goes thru it and the temp controls air flow.

Chilton says this cannot be fixed if bad, but then tells how to test it.
Take the lower half of the TB off, dip the ACV (only) in hot water to
see if it closes at 140° F. If not replace - the whole lower half it
looks like!

I am sure then, that the ACV is sold for - what? - maybe $2,000 or
$3,000 even! They gotcha on this part! ...Back to Pull-n-Save!

Also, the Idle Adjust Screw is on the lower half of the TB assembly.

Does this part ever need TLC? How does it work? Can crap get into
it and booger it up?

These are deeply troubling questions that only the anointed few can
answer......

DoctorBill

PS - the Venerated Chilton book says (p 5 - 10 & 11)
"The Fuel Pressure Regulator is calibrated at the factory and is not
serviceable. No attempt should be made to remove the regulator from
the Throttle Body. If the regulator is defective, the Throttle Body
must be replaced as an assembly"

Bullshit! Why do they sell FPR Diaphragms then? Who writes this
stuff and is it ever updated? Is that why the Factory put Loctite in
the screws? Why is the Diaphragm sold then?

I am cornfused....

[DOCTORBILL]

OK. But - I am thinking maybe I'll put the top half of the TB back on
(it isn't very hard to get off anyway) and see if the engine runs well THEN.

Then I'll test the Fuel Pressure.

If it still won't run, I'll take the TB apart again and go into the lower half
attached to the Intake Manifold.

I will check the ACV and have a look at how the Idle Adjust Screw works.

How does one check the Idle Control Solenoid? (IDS)

If I have the entire TB off, I might as well check the IDS while I'm there...

DoctorBill

[seb001]

If the IDS is simply a solenoid then applying 12V will confirm proper operation.

You can probably blow/suck air from the ports to confirm that there is no restriction (as you apply 12VDC)

I don't know if these device have a builtin diode so be carefull at polarity (or fuse your supply)

And thank you for extending your class room to the world.

Seb

[theragtopguy]

Go for it Dr. Bill, you are the man!