88 1500 5.0 throttle sticking closed

[smdk2500]

Correct - and I forgot to mention that.
But, the principle appears to be the same.

I checked mine yesterday because of what I'd read in this thread and didn't like the idea that the butterfly resting on the throttle body was the final stop and not the designated screw.
And was prompted to think it could have been as I'd messed around with it earlier (and the lock on it was already missing at that point) when I had a couple of occasions where the idle settled at 1500 rpm and wouldn't budge so thought it worth rechecking.

It's awkward as hell as the IAC seems to compensate, I couldn't read the tach, and hearing what's going on above the racket of the fan makes detecting rpm change difficult.
In the end, I wound it out , heard the rpm drop, experienced the sticking, wound it back in just enough for the rpm to rise a touch, checked the sticking was gone and quit there.

Im not familiar with the vortecs so I wasn't sure how there throttle body's work that is why I asked.

 

[Pinger]

Im not familiar with the vortecs so I wasn't sure how there throttle body's work that is why I asked.

A perfectly reasonable question to ask given at the time of posting I'd forgotten the OP has a TBI. And they do differ - the Vortec being single butterfly, the TBI dual.

 

[badco]

Cruise is unhooked.
Old Turbo 350. Vacuume kickdown.

Turbo 350 has a cable for kickdown. The vacuum is the modulator valve and isnt part of the kick down at all.

 

[badco]

Yep, I had it where, if you back out the screw too far the inner sleeve hooks on to the outer sleeve and makes it hard to depress the pedal. Here's my bored out 46mm with "Ultimate Mods" including shaved throttle shaft. I don't know if you can see it well enough in this pic but the blades are closed all the way. It relies totally on the IAC to control idle.

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Not talking about using the screw for the idle, using it to keep blades from hanging on the bore. Even your new one would hang if screw backed up to far when engine is running from the vacuum pull. Carbs do same thing and thats why even the back barrels on a holley have a adjustable screw. Have noticed that everyone woried about iac and noone even mentioned the tps adjustment

 

[Pinger]

Not talking about using the screw for the idle, using it to keep blades from hanging on the bore. Even your new one would hang if screw backed up to far when engine is running from the vacuum pull. Carbs do same thing and thats why even the back barrels on a holley have a adjustable screw. Have noticed that everyone woried about iac and noone even mentioned the tps adjustment

When I first went messing with mine TPS adjustment was what I was looking for but none there.
Mine's a Vortec though and TBI motor is the one being discussed on this thread.

 

[badco]

When I first went messing with mine TPS adjustment was what I was looking for but none there.
Mine's a Vortec though and TBI motor is the one being discussed on this thread.

They can be adjusted same as tbi

 

[Pinger]

They can be adjusted same as tbi

It's a while since I was there but from memory the mounting holes were perfectly round with no provision for adjustment.
And just had another look and it's as I remembered it - round, not slotted.

 

[PlayingWithTBI]

And just had another look and it's as I remembered it - round, not slotted.

On the TBI you just oval out the holes. You should be able to on the Vortec too.

 

[Pinger]

On the TBI you just oval out the holes. You should be able to on the Vortec too.

Ah - a bit of DIY trickery required!
By that measure though there's scarcely anything on the planet that isn't 'adjustable'.

 

[HotWheelsBurban]

Ah - a bit of DIY trickery required!
By that measure though there's scarcely anything on the planet that isn't 'adjustable'.

Yes especially if hammers or pry bars get involved LOL