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Do GT40P heads cause a check engine light?

  • Thread starter Thread starter Voice of Reason
  • Start date Start date Jan 25, 2007
V

Voice of Reason

New Member
Jun 25, 2003
70
0
0
Spring, TX
Jan 25, 2007
#1
  • Jan 25, 2007
  • #1
SO I've been searching this site and "the other" site for the past 1.5-2 hours (slow day at work, heh) and am only finding more questions than answers. I can't search for 'CEL' because it's too short a word, so hopefully me spelling out check engine will help someone out later when they go to do a search.

Anyway, I'm researching GT40P heads and because they do not have the thermactor ports on the back side of the heads you can't hook up part of the smog equipment to them. Everyone seems to say this won't cause a problem with the car running, but will it cause a CEL? If a CEL is on all the time even though the car is operating fine it will drive me crazy. If it does cause a CEL how do you disable it?

Thanks.
 
R

red95gtconvert

New Member
May 29, 2006
382
0
0
Ponca city, OK
Jan 25, 2007
#2
  • Jan 25, 2007
  • #2
My car has a gutted smog pump, the thermactor ports in the back of the heads are plugged and I have an offroad H pipe, also all of the tubing from the smog pump is removed. I have had no check engine lights or strange issues with the way the car runs so I think you will be good to go.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jan 25, 2007
#3
  • Jan 25, 2007
  • #3
The computer has no idea if the smog pump is there, if it's delivering air or anything else. The computer goes off the TAB and TAD being connected (which it seems you can cheat with a resistor if you remove them, though I have not personally tried it).

Good luck.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jan 25, 2007
#4
  • Jan 25, 2007
  • #4
*CEL or CEL*

Grady
 

Killer95Stang

New Member
Aug 7, 2003
256
1
0
Covina, CA
Jan 26, 2007
#5
  • Jan 26, 2007
  • #5
My GT40P heads were drilled for the Thermactor hookups on the back of the heads, so all the stock equipment fit perfect... Well, that was a while ago when my car still had smog equipment..
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
0
56
Republic, MO
Jan 26, 2007
#6
  • Jan 26, 2007
  • #6
final5-0 said:
*CEL or CEL*

Grady
Click to expand...


Good tip! Use the wildcard symbol to make it a 4 letter word.
 
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