What are these plugs for?

[jiho]

Depends if you have a dual-bed catalytic converter, or "three-way."

With dual-bed, an air pipe runs to the converter and is needed all the time for converter operation during normal driving. The computer assumes it's there, and adjusts the mixture differently than for "three-way."

With "three-way," the smog pump is only active during warm up, then it's switched out and does nothing. There's no pipe to the converter. The converter will work fine without it, and the computer won't know the difference (but will probably complain anyway).

Either one is in the way any time you have to get at anything.

EDIT: Also, on your Buick V6 no ports on the exhaust manifolds, a tube runs to the intake manifold behind the carburetor.

 

[jiho]

I just like the way older stuff looks when it’s all original.

You talk like a smog tech here in California.

 

[pontiacgp]

Everyone knows the flux capacitor didn't come out until 1985.

 

[565bbchevy]

Yeah I figure that and I really wouldn’t care but I can’t stand the way my engine bay looks.

Pulling out the N/A Buick V6 and putting in a V8 will make it look better also.

 

[Street Sweeper22]

Depends if you have a dual-bed catalytic converter, or "three-way."

With dual-bed, an air pipe runs to the converter and is needed all the time for converter operation during normal driving. The computer assumes it's there, and adjusts the mixture differently than for "three-way."

With "three-way," the smog pump is only active during warm up, then it's switched out and does nothing. There's no pipe to the converter. The converter will work fine without it, and the computer won't know the difference (but will probably complain anyway).

Either one is in the way any time you have to get at anything.

EDIT: Also, on your Buick V6 no ports on the exhaust manifolds, a tube runs to the intake manifold behind the carburetor.

With the smog pump missing do you think this is why it idles high? It starts right up and drives good but when I put it in gear it will chirp the wheels.

 

[Street Sweeper22]

Depends if you have a dual-bed catalytic converter, or "three-way."

With dual-bed, an air pipe runs to the converter and is needed all the time for converter operation during normal driving. The computer assumes it's there, and adjusts the mixture differently than for "three-way."

With "three-way," the smog pump is only active during warm up, then it's switched out and does nothing. There's no pipe to the converter. The converter will work fine without it, and the computer won't know the difference (but will probably complain anyway).

Either one is in the way any time you have to get at anything.

EDIT: Also, on your Buick V6 no ports on the exhaust manifolds, a tube runs to the intake manifold behind the carburetor.

With the smog pump missing do you think this is why it idles high? It starts right up and drives good but when I put it in gear it will chirp the wheels.

 

[Street Sweeper22]

Pulling out the N/A Buick V6 and putting in a V8 will make it look better also.

I really don’t have the cash for that or I would. I did see a turbo kit but I don’t know if my engine could support it.

 

[jiho]

With the smog pump missing do you think this is why it idles high? It starts right up and drives good but when I put it in gear it will chirp the wheels.

Doubtful. More likely causes:

1) Idle stop screw turned in too far.

2) Idle Speed Control (ISC) motor plunger nose switch dead. This causes the computer to leave the plunger fully extended, which keeps the idle high. You can check the switch with an ohm meter. (Less likely, the whole motor could be dead. Less likely still, the plunger could be turned out too far.)

3) Catalytic converter clogged up. This causes exhaust to blow back out the intake, which prevents the throttle plate from closing, which prevents the idle from going down.

My car had all three, and I dealt with them in that order.

 

[fleming442]

Doubtful. More likely causes:

1) Idle stop screw turned in too far.

2) Idle Speed Control (ISC) motor plunger nose switch dead. This causes the computer to leave the plunger fully extended, which keeps the idle high. You can check the switch with an ohm meter. (Less likely, the whole motor could be dead. Less likely still, the plunger could be turned out too far.)

3) Catalytic converter clogged up. This causes exhaust to blow back out the intake, which prevents the throttle plate from closing, which prevents the idle from going down.

My car had all three, and I dealt with them in that order.

My cat was gone when I got my car, yet the smog pump was intact. The tube to the cat was cut off near the same. It idled very high, and wouldn't come down until after driving, even a short distance. I never did fix it, but I wonder if that's what killed the driver side motor mount?

 

[oldsmobile joe]

Catalytic converter clogged up. This causes exhaust to blow back out the intake, which prevents the throttle plate from closing, which prevents the idle from going down.

huh? no, it doesn't happen that way. a clogged or restricted exhaust causes less air to enter the eng. in a n.a. eng, the air entering an engine is relatively equal to the air leaving an eng.
so the air doesn't blow back out of the intake, the piston just compresses whatever air is left in the cylinder. and since less or no air is leaving the cylinder, less or no more air can enter.
when this occurs in a vehicle with an o2 sensor, it may cause a rich code to set.
I'm still trying to get my hands around the idea that air, traveling in either direction can hold a throttle blade open.
joe