SN95 Smog Pump in A Fox?

Mhalc1

Member
May 10, 2021
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San Jose, CA
Greetings everyone, it is smog time for me and my smog pump seized up about a year ago... I have been just running a shorter belt and bypassed it but know i need one to pass smog. I read through this thread https://stangnet.com/mustang-forums/threads/how-to-install-fox-body-smog-pump-lots-of-pics.783109/ and saw dude used a fox pump in a sn95... both part numbers are still available but the foxbody went up from $79 15 years ago to over $300. The sn95 pump however i can do. Can anybody confirm this will work with my 1990 fox cardone 32-292 (https://shop.advanceautoparts.com/p/cardone-smog-air-pump-32-292/18980003-P?selectedStore=9891)
 
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My observation, you just have to deal with the discharge pipe, pull the pressed in pipe, replace with a core plug (freeze plug) and install bolt on discharge pipe pointed the same direction as it came off the fox pump.
Then, as they say, 'send it'.
Disclaimer: this is an observation and not based on any actual mechanical training.
 
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Pulley offset would be my concern. Even looking at the picture, that pump looks a lot shorter than the Fox pump.

Sn95 accessories are closer to the engine block than Fox.
 
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Just a question or two: you can’t find one in a salvage yard or via the salvage network? You would think these are easy to find, since most folks buy these cars and the first thing they do is strip these parts off. Why not post it in the parts wanted section here. And finally, as a CA neighbor, last time I had my truck in for its smog test, they didn’t open the hood. They plugged it in, saw no codes, and said I passed on that basis. Just my observation. Good luck.
 
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If he does have the original style cats on the car and needs to pass the sniffer, he will need the smog pump to inject oxygen into the cats to help with that process. He doesn't really clarify what "smog" entails for him however. My state doesn't pop the hood either, so all that stuff's been gone for years.


Youd think these pumps would be cheap. Many years ago I needed one and thought it would be easy to find one given that everyone tosses them out. Found some guy local who claimed he had a bucket of them in the shop because he "rips them off and throws them away". Showed up thinking i'd get a cheap pump and he wanted $100 for it. :mad:

Funny how all the throw-away parts suddenly become gold when they find someone who wants them.
 
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Just a question or two: you can’t find one in a salvage yard or via the salvage network? You would think these are easy to find, since most folks buy these cars and the first thing they do is strip these parts off.
Not sure about you younger fellas with the 80-90 Foxbodies, but back in the late 60's-70's these effin smog pumps went straight into the trash can.......
 
Just a question or two: you can’t find one in a salvage yard or via the salvage network? You would think these are easy to find, since most folks buy these cars and the first thing they do is strip these parts off. Why not post it in the parts wanted section here. And finally, as a CA neighbor, last time I had my truck in for its smog test, they didn’t open the hood. They plugged it in, saw no codes, and said I passed on that basis. Just my observation. Good luck.
Everytime i have smogged this car i have had to pass visual and the sniff test... i went once and the vacuum line to the smog pump was disconnected and it was a gross polluter... After realizing i reconnected it and went back and it passed... There are no Foxbody's in any junkyard near me and the only used one someone is selling is 2 hours away for $100 plus $20 shipping. i figured buying a new or remaned sn95 for that same price would make more sense.
 
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Just a question or two: you can’t find one in a salvage yard or via the salvage network? You would think these are easy to find, since most folks buy these cars and the first thing they do is strip these parts off. Why not post it in the parts wanted section here. And finally, as a CA neighbor, last time I had my truck in for its smog test, they didn’t open the hood. They plugged it in, saw no codes, and said I passed on that basis. Just my observation. Good luck.
I believe '99 and older they pop the hood and do a visual and sniffer test. 2000 and up, they just plug into the data port and don't do a visual or sniffer. Of course, just like the OP, I'm in one of the 'enhanced counties'. They do things different here (not better).
 
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Pulley offset would be my concern. Even looking at the picture, that pump looks a lot shorter than the Fox pump.

Sn95 accessories are closer to the engine block than Fox.
Is this true for the 5.0 sn95's? the part number says if fits the sn95 with the 5.0... I may just buy and try, learn and return.

Also my pulley is seized on mine it turns but gets hard at a certain point, maybe i can service mine... all i need is for it to pass smog and i can go straight back to a shorter belt to bypass it until next smog is needed.
 
Yeah, it's a pity. Just a month ago, I threw away the smog pump off my '93 thinking 'who would ever need this'. I had pulled the motor last year to transplant in my '54 and hung onto everything I didn't use. Last month I cleaned the garage and tossed a bunch of stuff. Dumb!
Could've delivered it too as I'm going to see my grandkids in Gilroy next week! Oh well.......spilled milk!

IMG_2751.JPG
 
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Is this true for the 5.0 sn95's? the part number says if fits the sn95 with the 5.0... I may just buy and try, learn and return.

I have no idea what the smog pump differences are, but in general the accessory drive for the 91-93 thunderbird, 94-95 Mustang and 96+ explorer are a lot shorter in terms of distance to the engine.

Buy a pump with a return plan in mind. I don't think it will work but i'm not 100-% sure
 
Yeah, it's a pity. Just a month ago, I threw away the smog pump off my '93 thinking 'who would ever need this'. I had pulled the motor last year to transplant in my '54 and hung onto everything I didn't use. Last month I cleaned the garage and tossed a bunch of stuff. Dumb!
Could've delivered it too as I'm going to see my grandkids in Gilroy next week! Oh well.......spilled milk!
Damn... oh well. I should have asked a few weeks earlier.
 
I have no idea what the smog pump differences are, but in general the accessory drive for the 91-93 thunderbird, 94-95 Mustang and 96+ explorer are a lot shorter in terms of distance to the engine.

Buy a pump with a return plan in mind. I don't think it will work but i'm not 100-% sure
Ok there is a local shop that carries the sn95 pump... i can check there return policy before i buy... if i cant get my hands on a foxbody pump in the next few weeks ill try it out, it seems like this could be a helpful experiment for us Californians.
 
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I remember reading that the smog pump was not needed in California. Doesnt it only work when cold and most people go in with a hot motor
I have tried a smog with a vacuum line on my smog pump accidently disconnected and one shortly after with it connected. the results were night and day. I believe it to be from the smog pump. I have explorer heads on my fox and i had to tap bolt holes to install the thermactor tube for visual, but i do not have any wholes like the e7 heads had. The reading below says those are engaged while the engine is warming up and at temp the smog pump helps the cats.

If anyone has legally passed CA sniff test without a smog pump let me know and ill give it another try.

"When the engine is cold, the thermactor air system pumps fresh air into the heads (there are bumps in each exhaust port in the head, air goes in from the back of the heads from the cross-over tube). When the engine is warmed up, the air is diverted to the cats which helps to create the catalytic reaction that converts hydrocarbons and carbon monoxide into C02 and water vapour." taken from (https://www.foxstang.com/fox-mustan...s,back of the heads from the cross-over tube).)
 
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I remember reading that the smog pump was not needed in California. Doesnt it only work when cold and most people go in with a hot motor
Someone is giving you erroneous information. A smog pump is required, especially on a '79-'93 Mustang. That's why CA has a visual inspection too. When the smog tech pops the hood and notices a missing smog pump (glaring omission), that would be an epic FAIL!
 
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"When the engine is cold, the thermactor air system pumps fresh air into the heads (there are bumps in each exhaust port in the head, air goes in from the back of the heads from the cross-over tube). When the engine is warmed up, the air is diverted to the cats which helps to create the catalytic reaction that converts hydrocarbons and carbon monoxide into C02 and water vapour." taken from (https://www.foxstang.com/fox-mustang-smog-system-help/#:~:text=SMOG pump (Thermactor Air System) This pump brings,back of the heads from the cross-over tube).)

The oxygen is what helps the cats heat up and become more efficient. That's why there is a big difference in test data when running the original cats with and without the air pump.


The reason air pumps fell out of use is two-fold. Engines began to operate much more efficiently, and cat converters became more effective and material compositions changed. That's why someone with a well-tuned engine and modern style aftermarket cats might pass the sniffer test with flying colors, where someone else might not. Lots of variables.

Because of those variables, most states just default to stock equipment and a visual to ensure stock parts are present. Takes the variability out of the equation.
 
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