G Man

I'm in the process of reinstalling emissions equipment in my 84'. The PO removed the cat and the air pump has been gutted. I am working with another lister to get a stock cat but not sure about the air pump situation. Will the cat still function as it should without an air pump or will it damage the system if not used?

SeanR

Why are you putting it all back on?

G Man

The car is for sale and emissions testing is required in surrounding areas. My city does not require testing at this time. I have a number of possible sales back out due to the car not having the emissions equipment installed.

SeanR

Ok, that makes sense. I'll keep an eye out for a pump for ya.

RCinXS

Have a pump, etc. sitting in the garage if you are in need.

But I have to say, the 84 it came off of, always passed emission without any of the air pump items installed at all.

brutus

Much depends on where you are and who is doing the testing. California being the very worst !

G Man

I would like the car to be Calif emissions compliant. I'm in NV but very close to Calif. Once I get a cat and working air pump back on the car it will be as it was from the factory and should be good for testing and inspection wherever. As stated before, there is an air pump on the car but it has no guts. It is just there for fan belt operation. Will cat still work properly if there is no air being pumped into it?

brutus

The 1980 USA cars had no air pump and used a cat and O 2 sensor.

ShawnSmith

If I understand the operation of air-pumps on cat-equiped cars properly, the goal is mostly related to cold-start emissions. The car is running rich during cold-start, thus adding air just ahead of the cats helps the reaction and raises temperatures in the cat more quickly, putting it into optimal operating region faster.

When warm, I don't think it's doing much.

Inspection-wise, a reasonably well informed tech will likely look for the airpump to be there are appear to be functioning. It's unlikely they'll have seen very many 928's, nor know how to prove whats going on inside the pump. Disconnected plumbing would be another matter.

Speedtoys

Worst for what? Whats wrong with runnin right?

danglerb

They don't insist it runs right, they insist that it has functioning 30 year old technology and that none of it no matter how useless in practice is altered or removed. A non working air pump and a old style cat I suspect will result in a much shorter life for the cat.

BTW CARB just ruled that by 2025 25% of available cars need to be zero emission or electric or something like that. Once more than half of drivers are in no fun basic transportation type cars I expect they will really drop the axe on anything fun.

tveltman

Meh. That presupposes that California will still have a government to enforce anything by 2025...

Don Carter

Check the rules in your area. In Houston we have very strict testing but none at all after a car turns 24.

brutus

California stopped the rolling 25 year exemption at 1975 so all the original smog equipment needs to be there plus the car is run under load on a dyno which never happened in the late 1970-1980s. Which really means the cars need to pass a much tougher test now than when new !