• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

KOER codes 44 & 94, just one quick question about them...

  • Thread starter Thread starter StreetDreamsGT
  • Start date Start date Mar 25, 2010

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Mar 25, 2010
#1
  • Mar 25, 2010
  • #1
I have been slowly reinstalling the smog equipment back on my car, but haven't gotten around to switching my off road h pipe to the catted one. Seeing how I haven't installed the tube that leads from the thermactor system down to the h pipe that could be the reason why I have the codes right?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 25, 2010
#2
  • Mar 25, 2010
  • #2
Nope, the Thermactor Air is monitored by the O2 sensors. So either the TAB or TAD solenoids are not functioning or one of the TAB or TAD valve are not working, or you dont have vacuum at the TAB or TAD valves. Or a clogged up crossover tube.
 

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Mar 26, 2010
#3
  • Mar 26, 2010
  • #3
Just seems kinda odd since I had been getting codes 41 and 91, then I found my vacuum leak and fixed it, now I'm getting 44 and 94. When I put the crossover tube back on I made sure to clean both opening and check to make sure air was getting through both, which it was. I should have both the tab and tad solenoids sitting around here I'll have to find them and swap them out to see if that fixes it. Should I expect any code due to the pipe from the thermactor sys to the exhaust not being there?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 26, 2010
#4
  • Mar 26, 2010
  • #4
If you dont have the TAB or TAD solenoid hooked up then those code will flash. Along with two other codes. Which you didnt post them up, so it seem that they are installed.

And thats perfectly normal for codes 94 and 44 to show up after a lean or rich code has been fixed. The 02s can only really detect one problem at a time. And in the event that the 02s are reading lean or rich, those codes take priority over the themactor codes( 94 and 44). So it cant detect the loss of thermactor air and a lean or rich code at the same time.

You need the smog system fully up and running to not throw codes 94 and 44. So you really need to figure out what is missing in the system. Which is normally a vacuum signal to TAB and TAD valves. Or one or the other. So make sure you have vacuum at the TAB and TAD valves. You can temporarily ground the negative side of the TAB and TAD solenoids to see if vacuum is being passed on like it should.
 

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Mar 26, 2010
#5
  • Mar 26, 2010
  • #5
I had read through one of the other threads you had posted in which had all the tests for how to check for errors in the system, so after I go through all that I'll let you know what I find out.

Thanks
 

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Apr 1, 2010
#6
  • Apr 1, 2010
  • #6
After I found my box of brand new ford sensors I went out and looked under the hood at the old ones... both the tab and tad solenoids were cracked no wonder I was having so many problems. I changed all three of the solenoids just for the heck of it and immediately she idled smoothly. I checked the codes and got the same ones... do I need to pull the battery and clear the old codes before I can check for any new codes?
 

joel5.0

Member
Jun 15, 2004
429
2
18
Puerto Rico
Apr 1, 2010
#7
  • Apr 1, 2010
  • #7
Nope..... codes 44 and 94 are KOER exclusive codes. IOW.... they are logged as part of the self test routine, they never get stored in memory.
 

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Apr 5, 2010
#8
  • Apr 5, 2010
  • #8
Ok I've been using this image to go over my thermactor system and make sure everything is hooked up properly, but this image isn't the way my system is set up. My Diverter Valve and bypass valve are reversed, the TAB is connected to the diverter valve and the TAD is connected to the bypass valve. Those colors don't correspond to my 92's wiring either so I'm not positive which solenoid is which, I'll tell you how it's all set up. The solenoid with a red and white/green wire connects to the bypass valve, the other solenoid with a red and a yellow/white wire connects to the diverter valve but like I said my bypass comes after my diverter valve... could this be my problem?
 

Attachments

  • attachment.GIF
    48.8 KB · Views: 220

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Apr 5, 2010
#9
  • Apr 5, 2010
  • #9
Solenoid with the Red and White/yellow wire goes to the TAB valve, and the other solenoid with the red and white/green goes to the TAD valve. So yours are crossed.
 

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Apr 5, 2010
#10
  • Apr 5, 2010
  • #10
Ok so I'll have to change them around and see if that fixes my error, what about having the valves reversed? Seems to me like that could cause a problem too, no?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Apr 5, 2010
#11
  • Apr 5, 2010
  • #11
TAB valve closer to the pump.
 

StreetDreamsGT

New Member
Mar 6, 2003
449
0
0
New Jersey
Apr 5, 2010
#12
  • Apr 5, 2010
  • #12
NICE! It worked, 11, I passed finally! Looks like I can finally put the Catted x pipe on and pass emissions. Thanks guys for all your help, couldn't have done it without you.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Apr 5, 2010
#13
  • Apr 5, 2010
  • #13
No problem Bud.
 
You must log in or register to reply here.

Similar threads

C
Engine Code 94 and 13
  • CmdrDerp
  • Nov 3, 2024
  • Fox 5.0 Mustang Tech
Replies
3
Views
318
Fox 5.0 Mustang Tech Nov 4, 2024
AeroCoupe
Engine Throwing codes 94, 33, 34, 44, and sporadic engine shutoff.
  • Ryu
  • Oct 9, 2024
  • Fox 5.0 Mustang Tech
Replies
11
Views
843
Fox 5.0 Mustang Tech Oct 16, 2024
89ripper
J
Thanks for the information on codes 31,34,44 and 94!
  • JK86LX50
  • Mar 5, 2025
  • The Welcome Wagon
Replies
3
Views
265
The Welcome Wagon Aug 5, 2025
gkomo
Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
Progress Thread Progress Thread- From6to8's 95 GT/Saleen Supercharged 331 install
  • from6to8
  • Mar 22, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
24
Views
721
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 6, 2026
from6to8
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?