I've tried searchign for J-rats Old thread but camer up with nothing. The car is a 90' N/A with the airpump removed. It failed because of hydrocarbons. Fairly new cat, New plugs, wires, oil and air filter.
It failed today, so we ran Seafoam through it, and cleaned the MAF. It runs alot smoother now and backfires less. But just to be on the safe side we're going to drop the idle, and Try to run Alcohol, I just wanted to know what kind to get. please help me and my Buddy out. He bought the car with no air pump, and we're not trying to replace it unless we absolutely have to.

Give me your best advice.

Thanks guys.

 

if the cat is stock, its probably toast from running without the air pump. Some aftermarket ones dont require an air pump, but the stocker does

 

Its a newer aftermarket cat with under 35K on it.

 

Get a high Flow cat.Even IF the car has Under 35K on it,the Rotary Engine can burn the **** out of it,rendering it Useless..My Opinion Get a NEW Cat..and Alcohol?..My choice is Whiskey!..J/K!..had to throw that in there..to ease Tension!..but for the car..Methyl hydrate or Denatured alcohol(Paint Store)..Oh and Put the damn Pump backl on!..you can run a Tube to the cat and dillute the Exhaust.By hooking the Pump Directly to the split air tube on the cat.

 

Yep i can garuntee your cat is toast from no air being pumpeb into it from the airpump.

 

ok this is how i passed, i got my tank of gas a little lower than 1/4 tank left, went to the hard wear store (sorry for spelling), get a gallon of denatured alcohol. pour it into the gas tank and then run the car hard to the emissions station, and hopefully you pass. all the alcohol does is make the car run hotter and cleaner, after that go fill your tank up with gas lol

 

i failed my emissions twice the other day. i have the cone filter with a breather in the air pump tube.. could that be why i failed? first test ran the car for maybe 5mins at 70mph on the way to the emissions test, after failing decided to warm up the car a lil, so i went 120mph for a couple mins then went back and tested again an my hydrocarbons were twice as worse. could my exhaust be toast an need replacing?

 

Need more info. I would try new plugs and oil change. Run 87 octane. Check for vac leaks.

To the OP: Get a smog pump. You should automatically fail if you don't have this on the car. I'm sure you could pickup everything really cheap on this site.

 

Question. Mazda designed the emmisions system with an airpump for the stock cat. You think this would be due to the how rich the rotary usually runs stock?

There is less air in the exhaust stream when the engine runs rich so an aftermarket cat that can usually run without an airpump due to the 14.7 AFR other engines try to run at, may not work on our cars due to how rich the engine runs right?

So basically, you think its absolutly required to have an airpump even with aftermarket cats due to the the reason our engines run rich?

I suppose if you tune the engine right you could possibly run aftermarket without an airpump..

Can anyone else chime in here?

 

^ Anyone?