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-   -   Installed new main cat not running the airpump to it though is that ok? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/installed-new-main-cat-not-running-airpump-though-ok-222256/)

RZRX7TT 09-09-03 04:09 PM

Installed new main cat not running the airpump to it though is that ok?
 
I just installed a low km main catalytic converter. I currently have my airpump disabled because i have removed the fuse to it, so that i can run the fans all the time to keep the engine cool. Now I will enable the airpump when i need to go for an air care test, but my question is if its ok to have the airpump not working with the main cat? it wont pose any damage or wreck the main cat will it?

ijneb 09-09-03 04:12 PM

No, unless you like a clogged cat.

vel525 09-09-03 04:13 PM

i think w/o the airpump the main cat will eventually get clogged. you should just get a pfc and a midpipe!! then you don't have to worry about a clogged cat and can completely remove the air pump.

YayeR 09-09-03 04:17 PM

i have a hi-flow cat that doesnt allow for the airpump, i just eliminated it entirely.

FormerPorscheGuy 09-09-03 05:40 PM

NO

Do a search, this topic has been discused many times.

Tim McCreary 09-09-03 06:45 PM

The air pump feeds fresh o2 to the Catalytic converter to chemically "burn" the unburned hydrocarbons (gas, oil). If you disable the air pump, you cause the cat to overheat and self destruct over time. Also note that the air pump should only work at low RPM's because at higher RPM's the engine is more efficient and hotter, therefore no need to have the extra O2 for burning excess fuel.

If you replaced your cat because it clogged, you have a problem and the new one will do the same regardless of the air pump function. If you pulled the fuse, then lost the cat later, you need to put the fuse back in.

Tim

maxcooper 09-09-03 06:55 PM

The injected air makes the cat hotter, not colder. The explanation that this burns off stuff that would otherwise accumulate and clog the cat makes sense to me, but I am not at all sure it is really true.

I have never heard a definitive answer to this question, so the jury is still out in my opinion.

-Max

Fritz Flynn 09-09-03 07:29 PM

Your fine :) Any cat will eventually go bad it may speed the process up a bit but not worth worrying about it.

cruiser 09-10-03 07:55 AM

So you can actually pass emmision tests without airpump attached ?

dubulup 09-10-03 08:00 AM


Originally posted by cruiser
So you can actually pass emmision tests without airpump attached ?
probably not.

RonKMiller 09-10-03 09:09 AM

Stolen from my Alldata.diy.com site for my Ford Van, and yes I pay for a subscription and yes, it's worth every nickle: ($14.95 a year!)

"In order to change HC and CO into harmless materials, the catalytic elements (platinum and palladium) start an oxidation, or burning, reaction in the catalytic converter. Oxidation is the addition of oxygen to an element or compound. If there is not already enough oxygen in the exhaust, a secondary air injection system is incorporated into the vehicle's design. This system supplies additional air to the oxidation catalyst. During the oxidation process, Oxygen (O2) mixes with the excess HC and CO to form H2O and CO2."

I don't think there is a chance in hell you can pass emissions without the airpump blowing in additional O2.
Cars are at their dirtiest when idleing or at low speeds, most modern lean burn engines could pass emissions at highway speeds without any kind of emission control system at all! Since you have the cat why not hook up the air pump and let it do it's thing so we can all breathe a little easier?

But to answer your question, no it won't hurt the cat, it just won't work, period. And if you are running your fans all the time to keep your engine cool you will soon be buying new fans. If your engine runs that hot you have other issues that need to be addressed or you will also be buying a new engine in the near future.

Tom93R1 09-10-03 09:51 AM

When I first got my FD it had the air pump but it wasnt hooked up. I failed emissions really really bad. This was on a cart with no air pump hookup. I had Meineke weld an inlet on the cat and hook the pump up and the emissions passed with flying colors. I believe the whole clogging thing is an old wives tale though, the only negative of no air pump is poor emissions.


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