89 Towncar CEL codes.

[Dibly74]

I replaced me "Check Engine" blub today and found that there are code I didn't know about. Got it done at Advance Auto Parts but they coulden't tell me what they meant. Here they are. I do know what the O2 sensor one means. They need replaceing being at 142K anyway. These might have something to do with my last post about the way it was acting. Anyone know what these mean?

KOEO Code 24
ACT/IAT/VAT Circuit
Out of range
During self test

Memory Code 41
HO2S (Sensor)
System lean
Bank 1

Memory Code 54
ACT/IAT/VAT Circuit
Above max voltage
-40 F indicated

[Dibly74]

So nobody knows what these codes mean.

[gadget73]

Probably means your intake air temperature sensor is toast. Its on the driver's side lower intake manifold, rearward of the #5 injector.

http://lunar.gadget73.com/images/galactica/parts_location/IAT_small.JPG

The code 41, hard to say. I would clear it and see if it comes back. It could mean a vacuum leak, or possibly a bad oxygen sensor.

[Dibly74]

Ahhh, thank you, I knew the car had an air temp sensor. I just never knew where it was on this car. I pretty much know the IAT sensor is bad cause every car I ever had threw a code for it. One question, is the passenger side O2 sensor hard to change, and should I do it from top or underneath?

[gadget73]

I don't know. I replaced the entire exhaust on my car and my O2 sensors aren't in the same place as stock. I would probably say from the top using the O2 sensor wrench and lots of penetrating lube. Change both sides if possible, if one is bad the other isn't much better. They have a service life of about 60k anyway.

[Dibly74]

Yeh, im gonna change both being at 142K. All the emissions tubes and other wiring are in the way on that side, so I was just wondering how hard it was to change.