code 54

[jet1]

hey can someone tell me how to check the vane air temp sensor? a week ago code 54 came up. Check engine light been on since. I have a mass air conversion, However i used the vane air temp sensor from the old vane airflow meter about 2 years ago and never had a code or problem. Thanks

[Stinger]

Typically it is easier to replace it with another sensor than to try and check voltages against air temp to see if it is reading correctly. Somewhere on the MAF sites they have the stock voltage vs temp specs for them though.

[jet1]

I tried everything today. Nothing. I still get code 54 and 81. checked everything,. When i unplug the act sensor it still gives code 54 first twice in row. I took the act out and cleaned. still no good. Well i cant find a sensor today so i will have to wait. Any other ideas. THis light comes on and stays on. It comes on a second after i start it. ANy other input.

[jet1]

does this make sense? When i went out this morning the first thing i did is clear and run codes , No ect sensor code, The car was never warmed up, instead i still get 54 twice.
I unplugged the tps,act,knock sensor and i still get code 54 twice even after i clear codes.
If i am understanding right code 54 is reffering to act sensor INPUT votage eceeds test maximum.
I also unpluged all sensors and ran codes and still get 54 no matter what i seem to do.
Is it possible to have a bad computer. Or is it possible the act sensor has to be working in order to continue systems pass and not throw code (plugged in or not) Other than this, Car seems to run ok.
What gets me is that if it is 54 input voltage eceeds test max, why when i unplug do i still get same code, Shouldnt it then give me a different code like code 24 vat sensor input out of test range? It sounds to me like the computer is giving it more voltage than required. Thanks for all you time guys.

[Stinger]

First of all, you've said vat, ect, and act in this thread. Those are three different sensors.

Code 54 refers to the ACT which is the "air charge temp" sensor located in the intake manifold and only used on 87-88 TC ecu's.

You're first few lines say you clear and ran codes, no ect (act) code, never warmed up, still got code 54 twice. What does this mean? First yous say no codes, then you say code 54 twice?

[jet1]

oh sorry, No i never said no codes, No i mean i went out in the morning and first thing i did was run codes, Got 54 twice. Why dont i get ect code considering it is not warmed up? So I looked at the wire diagram and decided to unplug act,ect,knock sensor, and tps, When i did this i still get code 54 twice, Nothing i do seems to matter. code 54 is always there and check engine light stays on. Considering aftter i unplugged all those sensors shouldnt i get some different code like 24 saying vat sensor is now out of range considering it is not even plugged in? Does this sound like a bad act sensor? I have never had one go bad. I do know i never experienced issues like this running codes with a code 54, if it is a bad act sensor it seems to have a pretty big affect on ecu as far as reading other codes when i unplug stuff.

[Stinger]

Though I've never tried it, I wouldn't guarantee unplugging sensors would throw codes for those sensors.

Are you sure the code is clearing when you try to clear it?

An ACT sensor is like 15 bux or free at the junkyard if you want to try a new one out.

[jet1]

no I am not sure it is clearing. Is there a way to tell? what other vehicles use the act sensor i need in a junk yard.

[jet1]

ok I found a act sensor and it was the problem (bad act sensor). THanks for all the input.