Hi all this is what I have going on. 1993 explorer with 184,000 miles.
Codes are koeo 172
Koer 172, 411, 538, 537
Now I know the 172 is an o2 sender. The 411 and 538 are rpm related so here is what I need
Is the 172 for the right side and is the passenger side?
The 411 and 538 rpm control what would cause that and how one would fix it.
What the heck is a 537 I can not find it in my Chilton or in the code readers book any idea what it may be.
I have been fighting this check engine light for months now always the same codes almost some times less never more that is.
I also have replaced all plugs and plug wires. The plugs were very worn with some light deposits but no carbon almost all looked to be burning lean but all were the same in wear and color. Any help is welcomed and thanks in advance also

 

o ya for got to add the truck also has a some what fast idel in park abd it go's up when ya put it in to gear then it drops back down if this helps any

 

I've never heard of a 537 code. For the RPM issue, try cleaning or replacing the IAC.

 

172 = lean signal on bank 1. Test the O2 before tossing it. You may have a vacuum leak, dirty MAF, maybe an intake mani gasket leak...whatever it is, you are getting to much oxygen in the air/fuel mix. If the O2 sensor tests bad, then toss it. Seeing how your spark plugs read, I'd look away from the sensor for now.


411 and 538 = be sure you have nothing like AC running (I imagine that's 411) and you have to GOOSE the pedal during the test that asks you to do so (it's tough, but you have to STOOOOMP the pedal for a moment to do that test)...

537 = try again with that one.


Bank 1 should be passenger side, based on the Ranger 4.0L diagram in the Haynes.

Looking at Google for "Ford OBD1 code 411", it seems a Probe website lists that as an IAC valve/circuit code. Hence, the lousy idle as mentioned already.

 

thanks I tryied to clean the IAC with carb cleaner . the os is only about two years old and with around 20,000 miles on it if that . the 537 has come up now three times and well never heard of it also like most i belive here. the giving it gas hmm not some thing i knew about or that my tester said to do so that new to me also will look in to it , replaced the plugs the other day and all were clean but very worn and showed a lean burn but again all 6 the same look . changed wires at the same time.used wd40 to check for gasket leack and shown nothing . tryied to clean the mas the best i could also the Iac. is there a better way to clean the IAC? removed the elect from the valve and sprayed it good but is there a link to show how to do it better ? is there a way to clean a o2 just in case . also find if i drive like a grandma check light dose not come one or if it dose after a bunch of miles but rap the gas and bingo lights on . hope this helps one of you smarter ones help me out and again thanks ahead of time for you trouble