Do I have bad oxygen sensors?

dashapht · 09-22-2001, 02:12 AM

I've been fighting a surging idle for a while now.. finally pulled the codes tonight.

I got "air/fuel mixture is out of range for self test"
and "EGO sensor reports lean air/fuel mixture"

The problem is that the car is running extremely rich (bad enough to burn your eyes) which would contradict with this reading. Could the O2 sensors be bad, thinking the mixture is lean, and dumping fuel in? then seeing the extra fuel, say "oops, im rich now!" take fuel away, and keep on doing that cycle, in turn causing a surge? this surging sucks!

thanks

------------------
93 Reef Blue Notchback, 74k miles (August 2001), TFS TW Heads, TFS Stage 1 Cam, TFS Track Heat Intake, 1.6 RR's, 70mm TB, Cold Air ,76mm MAF Meter, 24lb injectors, 255lph in-tank, AFPR, Edelbrock Water Pump, Be Cool Radiator, Mac 1 5/8" Long Tube Headers, 2.5" Pro Chamber, Flowmaster 2 CH 2.5" Cat Back, 3.73 , Alum Driveshaft, Auburn Differential, 17x9 Cobra Rs with Nitto 555s, Tri-Ax Shifter.
Got to make a pass finally! 8.44 @ 85mph on regular radials.
My new website: <A HREF="http:

jimberg · 09-22-2001, 09:45 AM

Replace your O2 sensors. It definitely sounds like they are bad.

------------------
351W 89 Mustang GT Convertible

PKRWUD · 09-22-2001, 02:18 PM

Have your exhaust checked too. A mixture that rich will clog up your cats in a matter of days.

Take care
~Chris

------------------
Retired Moderator
MustangNet

My site: JimPorterRacing

RACECAR spelled backwards is RACECAR

HEY !!! Are you ASE Certified ??? If you are, ask me about iATN. The best tool you'll ever have, and it's free !!!

dashapht · 09-23-2001, 12:55 AM

Thanks. I replaced my O2 sensors and lo and behold! the surge is gone!

------------------
93 Reef Blue Notchback, 74k miles (August 2001), TFS TW Heads, TFS Stage 1 Cam, TFS Track Heat Intake, 1.6 RR's, 70mm TB, Cold Air ,76mm MAF Meter, 24lb injectors, 255lph in-tank, AFPR, Edelbrock Water Pump, Be Cool Radiator, Mac 1 5/8" Long Tube Headers, 2.5" Pro Chamber, Flowmaster 2 CH 2.5" Cat Back, 3.73 , Alum Driveshaft, Auburn Differential, 17x9 Cobra Rs with Nitto 555s, Tri-Ax Shifter.
Got to make a pass finally! 8.44 @ 85mph on regular radials.
My new website: <A HREF="http

dashapht · 09-25-2001, 09:31 PM

Mmm.. Not only is the surge gone, but after resetting the battery and driving it for a few days, i can idle it down to 800 rpm and it sounds freakin MEAN. It used to surge so bad that i couldnt have the idle that low, cause it'd die. Man this thing lopes. It's almost as fun to sit at a stoplight as it as to drive it! ok maybe not, but you get the point. O2 sensors!

------------------
93 Reef Blue Notchback, 74k miles (August 2001), TFS TW Heads, TFS Stage 1 Cam, TFS Track Heat Intake, 1.6 RR's, 70mm TB, Cold Air ,76mm MAF Meter, 24lb injectors, 255lph in-tank, AFPR, Edelbrock Water Pump, Be Cool Radiator, Mac 1 5/8" Long Tube Headers, 2.5" Pro Chamber, Flowmaster 2 CH 2.5" Cat Back, 3.73 , Alum Driveshaft, Auburn Differential, 17x9 Cobra Rs with Nitto 555s, Tri-Ax Shifter.
Got to make a pass finally! 8.44 @ 85mph on regular radials.
My new website: <A HREF="http

PKRWUD · 09-26-2001, 06:11 PM

Feels pretty good when you figure it out, doesn't it!

Take care
~Chris

------------------
Retired Moderator
MustangNet

My site: JimPorterRacing

RACECAR spelled backwards is RACECAR

HEY !!! Are you ASE Certified ??? If you are, ask me about iATN. The best tool you'll ever have, and it's free !!!

09-22-2001, 02:12 AM	#1
dashapht Registered Member Join Date: Jan 2001 Location: nashville, tn Posts: 72	Do I have bad oxygen sensors? I've been fighting a surging idle for a while now.. finally pulled the codes tonight. I got "air/fuel mixture is out of range for self test" and "EGO sensor reports lean air/fuel mixture" The problem is that the car is running extremely rich (bad enough to burn your eyes) which would contradict with this reading. Could the O2 sensors be bad, thinking the mixture is lean, and dumping fuel in? then seeing the extra fuel, say "oops, im rich now!" take fuel away, and keep on doing that cycle, in turn causing a surge? this surging sucks! thanks ------------------ 93 Reef Blue Notchback, 74k miles (August 2001), TFS TW Heads, TFS Stage 1 Cam, TFS Track Heat Intake, 1.6 RR's, 70mm TB, Cold Air ,76mm MAF Meter, 24lb injectors, 255lph in-tank, AFPR, Edelbrock Water Pump, Be Cool Radiator, Mac 1 5/8" Long Tube Headers, 2.5" Pro Chamber, Flowmaster 2 CH 2.5" Cat Back, 3.73 , Alum Driveshaft, Auburn Differential, 17x9 Cobra Rs with Nitto 555s, Tri-Ax Shifter. Got to make a pass finally! 8.44 @ 85mph on regular radials. My new website: <A HREF="http:

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09-22-2001, 09:45 AM	#2
jimberg Registered Member Join Date: Oct 1998 Location: Rogers, MN Posts: 2,089	Replace your O2 sensors. It definitely sounds like they are bad. ------------------ 351W 89 Mustang GT Convertible

09-22-2001, 02:18 PM	#3
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Have your exhaust checked too. A mixture that rich will clog up your cats in a matter of days. Take care ~Chris ------------------ Retired Moderator MustangNet My site: JimPorterRacing RACECAR spelled backwards is RACECAR HEY !!! Are you ASE Certified ??? If you are, ask me about iATN. The best tool you'll ever have, and it's free !!!

09-23-2001, 12:55 AM	#4
dashapht Registered Member Join Date: Jan 2001 Location: nashville, tn Posts: 72	Thanks. I replaced my O2 sensors and lo and behold! the surge is gone! ------------------ 93 Reef Blue Notchback, 74k miles (August 2001), TFS TW Heads, TFS Stage 1 Cam, TFS Track Heat Intake, 1.6 RR's, 70mm TB, Cold Air ,76mm MAF Meter, 24lb injectors, 255lph in-tank, AFPR, Edelbrock Water Pump, Be Cool Radiator, Mac 1 5/8" Long Tube Headers, 2.5" Pro Chamber, Flowmaster 2 CH 2.5" Cat Back, 3.73 , Alum Driveshaft, Auburn Differential, 17x9 Cobra Rs with Nitto 555s, Tri-Ax Shifter. Got to make a pass finally! 8.44 @ 85mph on regular radials. My new website: <A HREF="http

09-25-2001, 09:31 PM	#5
dashapht Registered Member Join Date: Jan 2001 Location: nashville, tn Posts: 72	Mmm.. Not only is the surge gone, but after resetting the battery and driving it for a few days, i can idle it down to 800 rpm and it sounds freakin MEAN. It used to surge so bad that i couldnt have the idle that low, cause it'd die. Man this thing lopes. It's almost as fun to sit at a stoplight as it as to drive it! ok maybe not, but you get the point. O2 sensors! ------------------ 93 Reef Blue Notchback, 74k miles (August 2001), TFS TW Heads, TFS Stage 1 Cam, TFS Track Heat Intake, 1.6 RR's, 70mm TB, Cold Air ,76mm MAF Meter, 24lb injectors, 255lph in-tank, AFPR, Edelbrock Water Pump, Be Cool Radiator, Mac 1 5/8" Long Tube Headers, 2.5" Pro Chamber, Flowmaster 2 CH 2.5" Cat Back, 3.73 , Alum Driveshaft, Auburn Differential, 17x9 Cobra Rs with Nitto 555s, Tri-Ax Shifter. Got to make a pass finally! 8.44 @ 85mph on regular radials. My new website: <A HREF="http

09-26-2001, 06:11 PM	#6
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Feels pretty good when you figure it out, doesn't it! Take care ~Chris ------------------ Retired Moderator MustangNet My site: JimPorterRacing RACECAR spelled backwards is RACECAR HEY !!! Are you ASE Certified ??? If you are, ask me about iATN. The best tool you'll ever have, and it's free !!!