California Fox Smog Differences.

billison

I like tinted tail
15 Year Member
Feb 27, 2006
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short version. I'm seeing several people claim the foxes originally sold in cali had different/additional smog equipment. I've always been under the impression that all new foxes came with smog pumps and cats, and this is where I get hung up, that they all functioned the same.

Additionally , just for confirmation for what I believe I know, the air pipe on the cats is to allow the smog pump to pump air into the cats once warm to let them burn properly and not clog? And this specifically was standard?
 
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Most of the smog equipment regulation started in California, in the 60's new cars that were sold in California were equipped with smog stuff that was not installed in cars sold in other states, back then you couldn't register a non California car unless you installed the smog stuff.
Even today they restrict commercial trucks that enter their 'air space', I think it used to be if your commercial truck was built before a certain year you were restricted to how many times a year that truck could enter the state.
Thank's to the 'peoples republic of California' you can actually see the sun rise in LA
Disclaimer: the author makes no claim to the accuracy of this statement and no animals were harmed in the making of the paragraph.
 
short version. I'm seeing several people claim the foxes originally sold in cali had different/additional smog equipment. I've always been under the impression that all new foxes came with smog pumps and cats, and this is where I get hung up, that they all functioned the same.

Additionally , just for confirmation for what I believe I know, the air pipe on the cats is to allow the smog pump to pump air into the cats once warm to let them burn properly and not clog? And this specifically was standard?

Only CA difference was the '88s got MAF first. Other that that, all 49 states got the CA smog equipment standard. I believe I've seen window stickers state this.

Smog pump adds o2 to the cats to make them function more efficiently. Modern cats are very efficient, so that's why smog pumps got phased out. You won't clog the cats, but you may not pass a sniffer without one.

When cold, the pump pumps air to the tube in the back of the cylinder heads. The air exits the exhaust port and goes to the two lead cats which warm up first. This is for cold emissions.

Once warm, the diverted switches to the tube going to the main cats, to help with efficiency there.

The first two cats live most their life without the o2, and they don't clog.


These days, if you don't need a sniffer test and don't get a visual check, you can ditch the pump. If you put on new cats, you might even be able to pass a sniffer without it.
 
I miss the sun, surf, and tanned bikini bodies. I don't miss my smog pump, traffic, aholes, & cali libs

On topic, like others pointed out, MAF was mandatory from 88' and on. That's it.
 
Thank you for confirming what I knows.

Where there any foxes that were special to cali? I've had people claim some only came from there. One guy called my car a " true 88 California t top"
 
Thank you for confirming what I knows.

Where there any foxes that were special to cali? I've had people claim some only came from there. One guy called my car a " true 88 California t top"
I don't think there were any "Cali edition" vehicles back then for our Foxs like there are now. Only the 88' MAF cars. I allegedly had an original Cali MAF notch. It was not converted IMO. I don't think there is any special value there.
 
Got cha. Then nothing new. Just had a guy tell me I was making stuff up when I told him the smog pump helped the cats. He went on a rant about his 30 years working on cars and California Emisons , I showed him some jrichker screen shots and he blocked me.
 
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There was indeed a "California Emission System", regular production option (RPO) 422. There was also a "High Altitude Emission System", RPO 428. What extra pieces and parts those systems included I don't know.
  • RPO 422 = any non-exempt vehicle ordered through a CA dealer that is to be registered in CA
  • RPO 428 = any vehicle ordered in, and for principal use in, high alt areas (+5000')
There were also other 'emissions system' RPO #s..
  • RPO 423 = vehicles ordered through CA dealers to be registered out-of-state, i.e. CA emission system not required
  • RPO 93N = non-CA dealer orders for vehicles to be registered in CA (RPO 422 also required)
  • RPO 936 = CA emissions exempt, i.e. public service/emergency vehicles
  • RPO 429 = cars shipped to or ordered in non-high altitude areas for principal use in high altitude areas
 
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Got cha. Then nothing new. Just had a guy tell me I was making stuff up when I told him the smog pump helped the cats. He went on a rant about his 30 years working on cars and California Emisons , I showed him some jrichker screen shots and he blocked me.

Great info here ...If you have a minute, please check out my post in Gen Talk:
California Fox Body Owners- Need Help With Smog Check!