[Krem12]

Hi everyone,
Ive been having an idle issue when I coast to a stop where the car revs to about 2k RPM. I ran codes and got 94 and 44 which ive read means both of the Air Management Systems (EGR?) are inop. How do I fix this issue


I am using this thread here:
http://www.allfordmustangs.com/forums/5-0l-tech/30774-89-5-0-error-codes-44-94-a.html
to try and fix the issue. If anyone has anything else to add like a diagram, video or advice that would be greatly appreciated.


Edit: The car has not had any smog equipment removed that I am aware of. I did notice that the B/R slot on my vacuum tree has been capped off. I am not sure if that has an effect at all

 

[ALMOST STK]

code 44 - Secondary Air System Inoperative. bank one, passenger side
code 94 -Secondary Air Injection Inoperative. bank two, driver side




Code 44 RH side air not functioning.
Code 94 LH side air not functioning.

The computer uses the change in the O2 sensor readings to detect operation of the Thermactor control valves. When the dump valve opens, it reduces the O2 readings in the exhaust system. Then it closes the dump valve and the O2 readings increase. By toggling the dump valve (TAB), the computer tests for the 44/94 codes.

Failure mode is usually due to a clogged air crossover tube, where one or both sides of the tube clog with carbon. The air crossover tube mounts on the back of the cylinder heads and supplies air to each of the Thermactor air passages cast into the cylinder heads. When the heads do not get the proper air delivery, they set codes 44 & 94, depending on which passage is clogged. It is possible to get both 44 & 94, which would suggest that the air pump or control valves are not working correctly, or the crossover tube is full of carbon or missing.

 

[Krem12]

Thanks for the help ALMOST STK. Took the whole air system apart today and made sure everything worked. I did find that my solenoids were cracked but they were within spec according to my Chilton manual. I finally took off the air crossover tube and like you expected it was caked in carbon. Ill clean it out and hopefully this will fix my problems.

 

[Krem12]

Quick Update. Put the car back together and now both the Air bypass and Air diverter valves do not work when the car is at temp. Ordering new TAB and TAD solenoids.