confirmation on bad o2 sensors for a 98 ohv 2wd

[jrock02301]

po153 o2 sensor circuit no activity detected (bank 2 sensor 1)
po174 system too rich bank 2
po171 system too rich bank 1

these are the codes my explorer are giving me.

no drivability issues just poor mileage

can anyone confirm. and if it is true what sensors are the best to replace it with and the best place/for cost of the part?

thanks in advance.

 

[bigA]

Since you are getting both p0171 and p0174, I would suspect it's your intake gasket. I just had to replace mine a few months ago. The gaskets are pretty cheap, ~$30. Somewhat of a pain to get to them since you have to take the intake off. Do a quick search on the intake gaskets, there's a couple of writeups and some suggestions on where to get the gaskets. The p0153 error code does suggest an issue with the O2 sensor. So probably not a bad idea to replace that as well.

 

[blueka]

I need to replace both oxy sensors on my '97 SOHC explorer 4.0.. let me know what you come up with cos over here the sensors from ford are $200 each!!

Si

 

[ThePhoenix]

are you sure you NEED to replace them?

 

[blueka]

yeah...

Si

 

[jrock02301]

my cost is 62.75 for them at fomoco

and is there anyway to check the gaskets it runs great. just wanna make sure before i dig in and get in to something that isnt broke unless its a upgrade

also this maybe the wrong area to ask what is the main difference in the sohc and the ohv is interchangable?

 

[jrock02301]

also my readings on the computer shows that im getting 100% trim if it matters

P0153---O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1) [CURRENT]
Possible Cause:
l Heating inoperative.
l Wiring.
l HO2S
P0171---System too Rich (Bank 1) [CURRENT]
P0174---System too Rich (Bank 2) [CURRENT]
Possible Cause:
l Intake/exhaust leak.
l AIR system.
l MAF/VAF sensor
l Fuel pressure/pump.
l Injector(s).
l HO2S.

this is what i think are my possiblities

 

[bigA]

There is no easy way to check the gaskets without taking everything apart. And by that time, you might as well go ahead and replace them while you're there. The other thing to check would be to make sure that the intake is properly tightened down. If the bolts had worked loose, the seal may not be maintained even if the gaskets are good. There's a sticky post on doing the gaskets at the top of the forum:
http://www.explorerforum.com/forums/showthread.php?t=171819

There's no guarantee that it'll fix your problem, but is a very common issue.

 

[Turdle]

First of all-
po171 and po 174 indicate system too LEAN

your scanner has a glitch--

 

[jrock02301]

First of all-
po171 and po 174 indicate system too LEAN

your scanner has a glitch--

every book i check read too rich including my modis scanner, my old mt2500 and my mac taskmaster

 

[ThePhoenix]

I had those codes...and so far, my spark plug wire change has kept the light off (3 days and counting)...

i know its backwards thinking...you think that low spark means it would run richer...but maybe iff it has more fuel vapors, the engine thinks its Burning Lean...i dunno...but so far, it worked

thats why I asked if you were SURE its the sensors because 9 out of 10 times it isnt

 

[jrock02301]

well i replaced my plugs and wires, ran some seafoam, cleaned the maf, and iac. replaced the airfilter and changed the cats and muffler. all for preventative maintainence. the light was on before. now im just trying to stop making assumptions and get to the brass tax.