MRecio

Hey guys I have a 94 4Runner 3.0 auto with 153K and I threw a code last night... After checking it this morning it is flashing code 24. then code 27. im not sure what code 24 is but i think code 27 is O2 sensor.... am i right? the light didnt come back on today when i drove it around... (seeing if I could get it to come up again.... It does seem the truck runs rich... if it sits and idles u can start to smell the fumes... and it is getting terrible gas mileage...

So i think i have to replace the 02 sensor. should I replace both? and how can i tell they are bad?

AND WHAT IS CODE 24 lol

thook

http://www.off-road.com/toyota/tech/codes/

Test the AFM before replacing anything. Look in the factory service manual on how to. The FSM links are posted on the main forum page.

MRecio

I looked on the main page

http://www.toyotaparts.com/smg/main.php

that link is dead so i hope it wasnt the one you were talking about under it though thr is a link to download the manual for 10dollars... is this worth it? and is this what you were telling me to do to find out how to check my AFM... which has silicon around it as it has been taken apart before...()never noticed)


OK WAIT under the link it says for 97 and up.... so this isnt worth it for me as i have a 94..

thook

No, no...I mean look on the main forum page for "86-95 trucks and 4runners" where it says "Sticky: Links to FSM's".

Nevermind, though....here's the one you need....for free.
http://personal.utulsa.edu/~nathan-buchanan/93fsm/

Look under "Engine", then look for VAM (volume airflow meter) for the 3vze. It has instructions for how to test the operation....whether or not it is bad in one or more areas. Or, if your just not getting a good connection, signal, etc. You'll need an inexpensive digital multimeter.

BTW, they have silicon around the seal from the factory, anyway. So, it may not have been messed with. But, you'd know better than I....I can't see it.

MRecio

Ok i opened it up and the connections were bad.. they were just sitting there so i re soldered em but havent checked it with a meter yet but i started it and the truck idles much better but still run VERY rich... i am resetting the ECU to see if it was compensating for a bad AFM.... and see if resetting it will allow it to run normal. I will check it with a meter first thing in the morning tho.

If it still runs rich... do i have to replace te o2 sensor for the code 27? or can it be cleaned?

thook

You can try cleaning it. It wouldn't hurt. But, it may not be bad. That's why I suggested testing the AFM first. If it's running rich because of the AFM, then you may get an O2 signal just because of that. On the other hand, if the O2 sensor's not been replaced in a while, a whacky AFM may have pushed it over the edge causing it to go bad.