2150 Carb Question

[kbldawg]

Did broncos equiped with a MC2150 carb have the throttle Possitioning System?

I just bought one to replace my 2100 and it does not have the TPS, but my haynes manual shows that it should.

What does the TPS do?

Also, there is a vacuum port on the front of the carb at the top, where does that go to?

 

[Broncobowsher]

TPS is for fuel injection, not sure what they are doing putting that reference on a carburator. Now a throttle positioner (idle kicker solenoid) might be used. Sometimes called an anti-dieseling solenoid that closes the throttle completely when the power is off. Makes sure the engine really does stop with the key and not keep running (dieseling)

Vacuum port on the top of the carb, probably fuel bowl for evaperative emissions. Can't garantee that though.

 

[DirtDonk]

Some of the last 2100 carbs came with a TPS on them. Just rebuilt one today in fact. I think '82 or '83 may have been the first year, but not sure. They had just started using computers to control the spark, but still used a carburetor with feedback controls (not the Variable Venturi ones though).

So no Early Bronco came with one kbldawg. Like Broncobowsher was saying.
If the vacuum nipple you're referring to is a large one, like about 3/8" or so, it's actually a float-bowl vent and is connected to the charcoal cannister / evaporative emissions system. And some Broncos did have that.
I think that came in about '73 or '74. We were just discussing that very thing a couple of months ago. Your '70 may very well have come with the cannister, but probably did not use the bowl vent originally. A replacement carb may have it though, as they probably now sort of shuffle a lot of the early years together under a part number consolidation or something.
If yours was a CA truck, it "might" have had the bowl vent, but I still don't remember seeing any before about '73.

Paul