I got these codes tonight along with code 33 (EGR not functioning). I have no idea what these are. Can someone enlighten me as to what the AIR system is or AIR injection? I am wondering if these are contributing at all to my high idle/seemingly rich condition.
try a search - Jrichker has some real nice posts on 94/44 codes, as well as code 33 (IIRC). i wont even try - his posts are much clearer than what i can grunt out.
Code 33 - Insufficient EGR flow detected.
Look for vacuum leaks, cracked vacuum lines. Check to see if you have 5” of vacuum at the EGR vacuum connection at cruse RPM. Look for electrical signal at the vacuum regulator solenoid valve located on the rear of the passenger side wheel well. Using a test light across the electrical connector, it should flicker as the electrical signal flickers. Remember that the computer does not source any power, 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)
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)
Yes, thank you very much, you are very very helpful. So, it seems that as long as I don't have to test for emissions (which I don't), that these codes aren't really a big deal, right, as long as they aren't affecting the performance and reliability of the car? My idle seems to be fine now, so I am not going to pursue the cause of these codes any further.
HISSIN50, I don't have cats any more, but reguarding the detonation you mentioned. How would this cause detonation? Would a vacuum leak or bad EGR valve cause it?
HISSIN50, I don't have cats any more, but reguarding the detonation you mentioned. How would this cause detonation? Would a vacuum leak or bad EGR valve cause it?
detonation pertains to the EGR. the EGR allows spent, inert gasses into the chambers at part throttle/cruise. the puter dials in a ton of timing since the mixture is less volatile (with the inert gasses). if the EGR is removed, the mixture is more volatile and if the puter does not know that there is no EGR, timing will be advanced as if there were EGR gasses, and it can lead to detonation. some folks comment on the pinging, others say they have no issues.
that is why in my last post i said it 'can' lead to detonation - just something to keep an eye/ear on.