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People without the Thermactor Air "Smog" System

  • Thread starter Thread starter Jeff7477
  • Start date Start date Aug 25, 2005
J

Jeff7477

Founding Member
Jul 2, 2001
176
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0
Lincoln, Nebraska USA
Aug 25, 2005
#1
  • Aug 25, 2005
  • #1
I just pulled codes on my car, while the KOEO was clean, I got codes 94 and 44 on the KOER which are both for the thermactor system. I totally ditched it so I know I should be getting them, but does anyone else without it get them? Is there a way to make the computer think its there?

I'm not even sure what the computer looks at to see there is a problem with it.
 

Bottomlesspit

I started the longest tech thread in the known uni
Founding Member
Jan 1, 1999
2,636
2
48
Del Rio, TX
Aug 26, 2005
#2
  • Aug 26, 2005
  • #2
Jeff,
My old 93 GT did not have its thermactor air system and now my son's 92 hatch doesn't either. The EEC will throw those codes and I don't know of anyway to get rid of them. They were always present on my 93.
Basically there are the TAD and TAB solenoids that control the AIRB and AIRD valves. Since the solenoids are electrically hooked up to the EEC wiring harness, the EEC is looking for the correct hookup/signal from them. IF they are indeed removed, or not hooked up properly to the AIRB and AIRD valves, they are going to get a code.
Did you remove the solenoids along with the valves when you ditched the system? The solenoids have a vac line that runs to each of their control valves.
That's about all I remember about the system. Maybe someone else can add to this stuff. I really don't think the computer "looks" at anything other than whether the system is hooked up or not???
Ken
 

vikingpower

New Member
Dec 6, 2004
656
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0
CWU Ellensburg, WA
Aug 26, 2005
#3
  • Aug 26, 2005
  • #3
When I put my LT's and h-pipe in I took all that thermactor stuff out and plugged the hard line that leads from the cylinder heads. Runs right as rain, no codes or anything ever. My EGR is still hooked up though, if that helps. And my car is an '89 maybe it doesnt read as much stuff as the later Foxes?
 

r x F

New Member
Jun 6, 2005
8
0
0
Huntsville, AL
Aug 26, 2005
#4
  • Aug 26, 2005
  • #4
Jeff7477 said:
I just pulled codes on my car, while the KOEO was clean, I got codes 94 and 44 on the KOER which are both for the thermactor system. I totally ditched it so I know I should be getting them, but does anyone else without it get them? Is there a way to make the computer think its there?

I'm not even sure what the computer looks at to see there is a problem with it.
Click to expand...
There is no way to fool the computer into thinking the smog system is there (unless you can disable the system with a product such as the Tweecer). During the KOER, the computer tries to divert air into the exhaust manifolds. Doing so with a functioning AIR system will result in a lean condition from the O2 sensors. If a lean condition is not seen, the EEC will throw the 94/44 codes. If a lean condition is sensed, the EEC will then vary the valve actuations to make sure the AIRB/AIRD valves are working.
 
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