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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

help with CEL and O2 sensors

  • Thread starter Thread starter RysRed96GT
  • Start date Start date Jul 15, 2004

RysRed96GT

I like it FURRY!!!
Founding Member
Apr 9, 2001
3,207
0
56
Pasadena, MD
Jul 15, 2004
#1
  • Jul 15, 2004
  • #1
i've had a series of codes which started about 5 days after the headswap.

first was a p0175 (rich in bank 2)
then it was p0172 and 0175, rich in both banks, this happened twice.
and just today i had the same code twice, 0175 again.

my o2 sensors are stock with 114K miles and they've been through every thig with this car. im assuming my CELs are due to these bad sensors being clogged and contaminated. when i pulled them both they were white, which is silicone poisoning (not sure from what though). i only pulled the bank 1 sensor before i pulled the heads, leaving bank 2 in place the whole time.

the car doesnt seem as strong when its warmed up and doesnt feel consistant. i know the timing is perfect and the engine is physically fine. it feels the strongest shortly after i start it up, but then as it gets warm it doesnt feel as strong by a slight margin (though its still stronger than before).

u cleaned my MAF, changed my plugs to platinum autolites and changed my wires. my only guess is the O2's becausr if i was actually rich (knowing that the sensors arent read at WOT), i would get consistant readings on my sensors, but im not. sometimes bank 2 is "rich", sometimes both. i know that if a sensors is bad and/or aging it will think it's rich because not enough oxygen is getting onto them, and hence leaning out the mixture on its bank. the CEL only turns on after 3 or more complete warmed up drives.

all signs point to bad sensors, but can anyone else back me up? they cost 70 bucks each and i havent put them on yet. just want to make sure cuz if not i'll return them. thanx to any replies!
 

Dark Knight GT

I can't get it up......ok that didn't sound right.
May 26, 2003
3,653
2
56
Ozark, Missouri
Jul 16, 2004
#2
  • Jul 16, 2004
  • #2
It sounds to me that after 114k miles and the hell you've probably put them through, its time for a new set of o2 sensors. I'de check with Randy Stinchcomb over at www.modulardepot.com under the Ford parts section in their forums and just see what price he can get o2 sensors for before I'de invest in a set and pay 70 bucks a piece. He's a great guy to work with and can get some pretty good deals on Ford parts.

BTW, platinum plugs aren't exactly "performance plugs" but more or less a mileage plug. Most of the racers I know use copper plugs and change them out every year for best results.
 

RysRed96GT

I like it FURRY!!!
Founding Member
Apr 9, 2001
3,207
0
56
Pasadena, MD
Jul 16, 2004
#3
  • Jul 16, 2004
  • #3
Dark Knight GT said:
It sounds to me that after 114k miles and the hell you've probably put them through, its time for a new set of o2 sensors. I'de check with Randy Stinchcomb over at www.modulardepot.com under the Ford parts section in their forums and just see what price he can get o2 sensors for before I'de invest in a set and pay 70 bucks a piece. He's a great guy to work with and can get some pretty good deals on Ford parts.

BTW, platinum plugs aren't exactly "performance plugs" but more or less a mileage plug. Most of the racers I know use copper plugs and change them out every year for best results.
Click to expand...
agreed. i already bought the new sensors from randy actually (his dealership is very close to my house).

and yeah, platinum plugs arent best for performance. i had coppers before but they had like 10K miles on them. i tried platinums just for the hell of it. coppers do give a better spark so i'll prolly do that next and keep my platinums for a later date once i get this all working.

im hoping this is my answer
 

Dark Knight GT

I can't get it up......ok that didn't sound right.
May 26, 2003
3,653
2
56
Ozark, Missouri
Jul 16, 2004
#4
  • Jul 16, 2004
  • #4
If that doesn't clear it up, I'de almost say you need a dyno tune to get the a/f ratio correct and the ignition as precise as possible.
 

fstnfuriusgirl

Banned
May 3, 2003
33
0
0
Maryland
Jul 16, 2004
#5
  • Jul 16, 2004
  • #5
<---rysred96

its fixed

apparently it was the sensors. it's been through 5 closed loops and still no CEL. i feel a definate difference in response. sounds a little healthier too. pinch more pull too i'll add. overall car feels healthy again.
 

RysRed96GT

I like it FURRY!!!
Founding Member
Apr 9, 2001
3,207
0
56
Pasadena, MD
Jul 16, 2004
#6
  • Jul 16, 2004
  • #6
nevermind, its not fixed...now im stumped
 
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