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Hello I have a 2000 explorer xls 4.0 sohc and i have a loss of power the engine act's like it has a bad plug real slugish then all of a sudden it will respond correctly. The service engine light came on so i scanned for problem and it came up with 5 error codes cyl. 4,5,6 misfire.Also code p0175 rich bank #2, and code p1152 . I have changed plugs and wires and fuel filter and of course i still have same problem no more service light just poor acceleration mainly.. Any input would be much appriciated.
Thank You

 

you have not fixed the problem. Lets see if this works. (OK, its not, I'm gonna have to make this as multiple post.)

Heated Oxygen Sensor (HEGO), Catalyst, & Fuel Sys Monitor Related Diagnostic Trouble Codes TSB 01-9-7 by Ford for 96

4/10/03

ISSUE: This article is intended to be an aide in diagnosing conditions related to Heated Oxygen Sensor (HO2S), Catalyst, and Fuel System Monitor related Diagnostic Trouble Codes (DTCs). Additional information is included to assist in diagnosing certain vehicle symptoms. This article is NOT intended to be a shortcut to the Powertrain Control/Emissions Diagnosis (PC/ED) Workshop Manual pinpoint tests. The pinpoint tests in the PC/ED Manual should ALWAYS be followed when diagnosing vehicle conditions.

ACTION: Use the following information and Service Tips to assist in the diagnosis of HO2S, Catalyst, and Fuel System Monitor related DTCs.

INDEX
A. Description of Terms and Acronyms
B. HO2S Location Diagrams
C. Heated Oxygen Sensor (HO2S) Monitor
C1. Heated Oxygen Sensor (HO2S) Monitor - Information
C2. Heated Oxygen Sensor (HO2S) Monitor - Diagnostic Trouble Codes (DTCs)
D. Catalyst Efficiency Monitor
D1. Catalyst Efficiency Monitor - Information
D2. Catalyst Efficiency Monitor - Diagnostic Trouble Codes (DTCs)
E. Fuel System Monitor
E1. Fuel System Monitor - Information
E2. Fuel System Monitor - Diagnostic Trouble Codes (DTCs)
F. Diagnostic Service Tips
F1. Tips - General
F2. Tips Related to Heated Oxygen Sensor (HO2S) Monitor
F3. Tips Related to Catalyst Monitor
F4. Tips Related to Fuel System Monitor
A.) Description of Terms and Acronyms
CHT - Cylinder Head Temperature Sensor or PID
CKP - Crankshaft Position Sensor or PID
DTC - Diagnostic Trouble Code
ECT - Engine Coolant Temperature Sensor or PID
EGR - Exhaust Gas Recirculation
EEC - Electronic Engine Control
EVR - EGR Vacuum Regulator
FMEM - Failure Mode Effects Management
GND - Ground
HC - Hydrocarbons
HO2S - Heated Oxygen Sensor or PID
IAT - Inlet Air Temperature Sensor or PID
KAM - Keep Alive Memory
KOEO - Key On Engine Off
KOER - Key On Engine Running
LONGFT - Long Term Fuel Trim
MAF - Mass Air Flow Sensor or PID
MIL - Malfunction Indicator Lamp ("Check Engine")
NGS - New Generation Star Tester (Scan Tool)
OBD II - On-Board Diagnostics II
OSM - Output State Monitor
PC/ED - Powertrain Control/Emissions Diagnosis
PCM - Powertrain Control Module
PCV - Positive Crankcase Ventilation
PID - Parameter Identification Display
RAM - Random Access Memory
RPM - Revolutions Per Minute
SHRTFT - Short Term Fuel Trim
Stoichiometric - 14.7:1 Air/Fuel Ratio (Gasoline Engines)
TPS - Throttle Position Sensor or PID
VMV - Vapor Management Valve
VPWR - Vehicle Power (Battery Voltage)
VREF - Vehicle Reference Voltage (5 volts)
B.) HO2S Location Diagrams

Refer to Figure 1 to better understand the HO2S sensor names and locations. Regardless of how the engine is mounted in the vehicle, conventional or transverse, the HO2S naming convention stays the same in relationship to engine banks 1 and 2. Bank 1 will always be the bank containing the #1 cylinder.

C.) HEATED OXYGEN SENSOR (HO2S) MONITOR

C1.) Heated Oxygen Sensor (HO2S) Monitor - Information

The HO2S Monitor is an on-board strategy designed to monitor the HO2S sensors for a malfunction or deterioration that can affect emissions. Under specific conditions, the fuel control or upstream HO2S sensors ( Figure 1 and Figure 3 ) are checked for proper output voltage and response rate (the time it takes to switch from lean to rich or rich to lean). Downstream HO2S sensors (Figures 1 and 3) used for Catalyst Monitor are also monitored for proper output voltage. Input is required from the ECT or CHT, IAT, MAF, TP and CKP sensors to activate the HO2S Monitor. The Fuel System Monitor and Misfire Detection Monitor must also have completed successfully before the HO2S Monitor is enabled.

The HO2S sensor senses the oxygen content in the exhaust flow and outputs a voltage between zero and 1.0 volt. Lean of stoichiometric (air/fuel ratio of approximately 14.7:1 for gasoline engines), the HO2S will generate a voltage between zero and 0.45 volt. Rich of stoichiometric, the HO2S will generate a voltage between 0.45 and 1.0 volt.

The HO2S Monitor evaluates both the upstream (Fuel Control) and downstream (Catalyst Monitor) HO2S for proper function.

Once the HO2S Monitor is enabled, the upstream HO2S signal voltage amplitude and response frequency are checked. Excessive voltage is determined by comparing the HO2S signal voltage to a maximum calibratable threshold voltage.

A fixed frequency closed loop fuel control routine is executed and the upstream HO2S voltage amplitude and output response frequency are observed. A sample of the upstream HO2S signal is evaluated to determine if the sensor is capable of switching or has a slow response rate.

An HO2S heater circuit fault is determined by turning the heater on and off and looking for a corresponding change in the OSM and by measuring the current going through the heater circuit.

The MIL is activated after a fault is detected on two consecutive OBD II drive cycles.

The HO2S Monitor DTCs can be categorized as follows:

HO2S signal circuit malfunction - P0131, P0136, P0151, P0156
HO2S slow response rate - P0133, P0153
HO2S heater circuit malfunction - P0135, P0141, P0155, P0161
Downstream HO2S not running in on-demand self test - P1127
Swapped HO2S connectors - P1128 and P1129
HO2S lack of switching - P1130, P1131, P1132, P1150, P1151, P1152
HO2S lack of switching (sensor indicates lean) - P1137
HO2S lack of switching (sensor indicates rich) - P1138
C2.) Heated Oxygen Sensor (HO2S) Monitor - Diagnostic Trouble Codes

HEATED OXYGEN SENSOR (HO2S) MONITOR - HO2S LACK OF SWITCHING Diagnostic Trouble Code Description
Possible Causes

P1130 - Lack of HO2S-11 Switch, Fuel Trim at Limit
The HEGO Sensor is monitored for switching. The code will set when the HO2S fails to switch due to circuit or fuel at or exceeding a calibrated limit.

Electrical:
· Short to VPWR or VREF in harness or HO2S
· HO2S circuit shorted to Ground
· Water in harness connector
· Open circuit
· Corrosion or poor mating terminals and wiring
· Damaged HO2S
· Damaged PCM (other DTCs should be present)

Fuel System:
· Excessive fuel pressure (stuck fuel pressure regulator, restricted fuel return lines, etc.)
· Leaking/contaminated fuel injectors or fuel pressure regulator
· Low fuel pressure or running out of fuel (fuel pump concern, fuel supply line restrictions, low fuel level, etc.)
· Vapor recovery system (stuck VMV, etc.)

Induction System:
· MAF contamination
· Air leaks between MAF and throttle plate
· PCV system / Other vacuum leaks
· Improperly seated engine oil dipstick

EGR System:
· Leaking gasket
· Stuck EGR valve / Leaking diaphragm or EVR

Base Engine:
· Oil overfill
· Incorrect cylinder compression
· Exhaust leaks before or near the HO2S
· Secondary air stuck on


HEATED OXYGEN SENSOR (HO2S) MONITOR - HO2S LACK OF SWITCHING Diagnostic Trouble Code Description Possible Causes

P1131 - Lack of HO2S-11 Switch, Indicates Lean When an HO2S sensor indicates lean at the end of a test, the system is trying to correct for an over-lean condition. The code is set when the fuel control system no longer detects switching for a calibrated amount of time. See Possible Causes for DTC P1130

P1132 - Lack of HO2S-11 Switch, Indicates Rich When an HO2S sensor indicates rich at the end of a test, the system is trying to correct for an over-rich condition. The code is set when the fuel control system no longer detects switching for a calibrated amount of time. See Possible Causes for DTC P1130

P1137 - Lack of HO2S-12 Switch, Sensor Indicates Lean The downstream HO2S sensors are forced rich and lean and monitored by the PCM. The code is set if the PCM does not detect the output of the HO2S in a calibrated amount of time.
· Pinched, shorted or corroded wiring and pins
· Crossed sensor wires
· Exhaust leaks
· Contaminated or damaged sensor
P1138 - Lack of HO2S-12 Switch, Sensor Indicates Rich Same as DTC P1137, but indicating rich. See Possible Causes for DTC P1137

P1150 - Lack of HO2S-21 Switch, Fuel Trim at Limit Same as DTC P1130, but opposite bank. See Possible Causes for DTC P1130
P1151 - Lack of HO2S-21 Switch, Indicates Lean Same as DTC P1131, but opposite bank. See Possible Causes for DTC P1130

P1152 - Lack of HO2S-21 Switch, Indicates Rich Same as DTC P1132, but opposite bank. See Possible Causes for DTC P1130

 

Well its giving me grief to post the rest, so its found here

http://home.comcast.net/~miesk5/tech..._bulletins.htm

under; Heated Oxygen Sensor (HEGO), Catalyst, & Fuel Sys Monitor Related Diagnostic Trouble Codes TSB 01-9-7 by Ford for 96<O:P> </O:P>

 

Thank's for all the great info. So it looks like i am going to replace the o2 sensor first. My truck has two should i replace them both or witch one?


Thank's again this issue has been driving me crazy trying to figure out the problem..

 

Noooooooo!
I don't know why but a whole load of people who get a fault code for a sensor just go and buy a new sensor then find nothing's changed. That's because there was nothing wrong with the old sensor.

If you re-read what 01silvergt posted, there are 22 possible causes just for P1152 alone ("see possible causes for P1130" right at the bottom). Swapping out the sensor is only 1 of them and is one of the least likely!
So, you can guess and buy the sensor anyway
OR
Work your way through ALL of the possible causes one by one; some are easy, broken or shorted wires and the like, some trickier but none impossible for a home mechanic.

I'd be checking the voltage to the sensor first as that's a common fault when they get a few years onto them, just clean out the corrosion from the plug and make sure you refit it tight then work your way through all of the other checks that you can and see where that gets you.

It MIGHT be the sensor but at this point it's impossible to tell and pointless swapping it unless you have a spare and don't need to buy a new one to do it.

The haynes manual is pretty good for this kind of diagnostic but take no notice of them when they say that things like the MAF can't be cleaned and must be replaced; there are posts here that prove otherwise.

Good luck.

 

Yes i will re-read and start at the top and work my way through the possible causes. The reason i was quick to jump to the o2 sensor is because everybody and there mother is telling me that's the problem. But this problem is taking for ever to resolve and it has been really discouraging. But with the good info i will take my time and work through and find the problem instead of just changing part's till i get lucky.

Thank's for the help..

 

It's always easy to give advice when it's not your problem!

But seriously, I had a bunch of really tricky problems that almost had me throwing thousands away. It was the guys here in this forum who put me straight and I ultimately fixed it all up myself for very few bucks. Most regular posters are very experienced and some are master techs, yet others have access to Ford's tech bulletins and other documents that we mere mortals simply aren't meant to see. All give their time and advice freely.

So you can listen to everybody and their mother, and maybe you should if they're qualified auto techs, or you can read all about how the MANUFACTURER of your vehicle tells their own dealerships how to diagnose your problem, which is exactly the information that 01silvergt posted for you and go from there.

It's your call; good luck with it.

 

The o2 sensor was bad on the 4,5,6, cylinder side not sure witch one that is. I figured it out by swapping the two front sensors out since the error kept coming back as too rich bank 2. So after i switched the sensors error code came back as too rich bank 1. No problems since i changed the o2 sensor i have driven 125 miles so far and is running great ..
Thank you
allen1010 and 01silvergt