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h-pipe to smog pump?

  • Thread starter Thread starter rd02gt
  • Start date Start date Sep 3, 2004

rd02gt

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Mar 23, 2004
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Brea, CA
Sep 3, 2004
#1
  • Sep 3, 2004
  • #1
Well i bought a car, and didnt relize it was missing a bunch of things... long story! Anyways what is the pip called that runs from the stock h-pipe to the smog pump or something like that, and where can i get it? thanks
 

jrichker

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#2
  • Sep 3, 2004
  • #2
I got mine at Advance Auto Parts. I told the I wanted the pipe that ran form the check valve to the cat converter. If you don't have the pipe, the check valve may also be missing too.

Here's some general smog pump system info...

The smog pump has two vacuum operated valves. The first valve either dumps the pump output to the open air or directs it to the next valve. The smog pump dumps its output at full throttle to save horsepower. The second valve directs the air to either the passages in the heads or to the tube that runs to the cat converters. Both the tube for the head and the tube going to the cat converters have one way check valves to prevent the hot exhaust gas from backing up into the tube and the control valves.

Here are some of the codes generated by faulty parts in the smog pump system and their fixes...

Codes 94 & 44 - Check vacuum lines for leaks, & cracks. Disconnect the big hose from smog pump: with the engine running you should feel air output. Reconnect the smog pump hose & apply vacuum to the first vacuum controlled valve: Its purpose is to either dump the pump's output to the atmosphere or pass it to the next valve. The next vacuum controlled valve directs the air to either the cylinder heads when the engine is cold or to the catalytic converter when the engine is warm. Disconnect the big hoses from the back side of the vacuum controlled valve and start the engine. Apply vacuum to the valve and see if the airflow changes from one hose to the next.

The two electrical controlled vacuum valves mounted on the rear of the passenger side wheelwell turn the vacuum on & off under computer control. Check to see that both valves have +12 volts on the red wire. Then ground the white/red wire and the first solenoid should open and pass vacuum. Do the same thing to the light green/black wire on the second solenoid and it should open and pass vacuum.

Remember that the computer does not source power for any actuator or relay, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/t...inks-ign-ac.gif

http://www.veryuseful.com/mustang/t...91eecPinout.gif

Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The secondary air diverter valve (rear vacuum operated valve) isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve. The solenoid valve is located on the back side of the passenger side wheel well. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.

See http://www.veryuseful.com/mustang/t...ng5.0Vacuum.gif for help on the vacuum line plumbing.


Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. The dump valve air diverter valve (front vacuum operated valve) isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve Check the solenoid valve for +12 volts at the Red wire and look for the Red/White wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the Red/White wire for the solenoid valve.
 

rd02gt

New Member
Mar 23, 2004
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Brea, CA
Sep 4, 2004
#3
  • Sep 4, 2004
  • #3
so do you know what that "tube" is called?
 

5o5speed

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Aug 9, 2004
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Sep 4, 2004
#4
  • Sep 4, 2004
  • #4
I would just delete your entire smog system since it sounds like someone has already begun the job for you. I had the same situation as you when I bought my 91 GT recently (my pipe was cut from the H too). My car still passed an emissions inspection without it connected though. So now I'm going to take all the rest of the stuff off including my smog pump. True, no real horsepower benefit but it will clean up the looks of the engine compartment.
 

jrichker

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#5
  • Sep 4, 2004
  • #5
Try air tube (?). I just told them I wanted the tube that ran from the smog pump in the engine compartment to the cat converters.
 

rd02gt

New Member
Mar 23, 2004
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Brea, CA
Sep 4, 2004
#6
  • Sep 4, 2004
  • #6
so ifyou are getting rid of it, would you wanna sale it? or how much does one cost?
 

jaidedeye

Member
Apr 4, 2004
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Goldsboro nc
Sep 4, 2004
#7
  • Sep 4, 2004
  • #7
couldnt you just run a pipe straight from the smog pump to the cats and get rid of the valves and crap that goes to the back of the heads?
 
S

stang*vs*deer

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Feb 26, 2004
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Sep 4, 2004
#8
  • Sep 4, 2004
  • #8
I can't remember the name for that part, but when I put in my Bassani X pipe the original pipe wouldn't fit anymore (I would give it to you, but I hacked it up trying to make it fit...just would not line up correctly)...so I replaced it with Hi-Temp Silicone hose. Worked perfectly! Can pick that up at almost any Auto parts store. I believe 3/4 inch did the trick.
 

rd02gt

New Member
Mar 23, 2004
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Brea, CA
Sep 4, 2004
#9
  • Sep 4, 2004
  • #9
sweet, thats what i was thinking but i wasent sure if it was special or anything!. thanks alot for the input, and if anyone finds out the name of that specific tube. email me or post it up.!! thanks alot!
 
S

shorty1993

New Member
Apr 16, 2004
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Gadsden, AL
Sep 5, 2004
#10
  • Sep 5, 2004
  • #10
i have all the original parts. smog pump, steel line (from h-pipe to pump), all silicone hoses, and valves. everything you need to put it back original. you may also want to check the backside of the passenger strut tower to make sure the silonoids are still there, i have those as well. here is a before and after pic so you can see what silonoids went to that. feel free to email or PM me.

before:you can see the gray tops of the silonoids.


after: wire hiding just started so it aint perfect yet.
View attachment 522896
 

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