'96 993 C2 Oxygen Sensor Replacement?

[993Coupe]

Hey all,

I just purchased a 96 C2 coupe and everything is great EXCEPT....I can't pass inspection because I have a CEL. The code reads P1117 - which has something to do with the O2 sensor(s) reading below the threshold. Being new to Porsche (but not new to engine repair in general), is this something I can change out fairly easily to save a few bucks or should I let the professionals handle it? ($$$$)

Any thoughts or suggestions would be greatly appreciated!!

Thanks

[ischmitz]

Where does the P1117 fault code come from - are you using a generic OBD-2 code reader? You might want to use the WSM procedure to read the fault code by counting the flashes on the CEL.

Also, read here: SAI CEL FAQ

It explains one possible reason for the CEL on 96' and later 993 and how to deal with it. To my knowledge the 993 codes related to the O2 sensor are:

1_22: Check sensor signal
This code is shown if the signal is not plausible and the O2-sensor is tired.

1_23: Oxygen regulation stop
This code is thrown if the mixture correction has reached the upper or lower limit. Typically, air leaks or leaking injectors

1_24: Oxygen sensor short to +/GND
This code is thrown if the O2 sensor signal is below 100mV or above 1400mV.

Cheers,
Ingo

[993Coupe]

I was using a DashDAQ to read the codes. It spit out the P1117 code when I ran a diagnostic. I had a trusted Porsche specialist check the codes when I did a PPI cause I was worried about the SAI fault. Luckily it was not that. Pretty sure it has to do with the O2 sensors.

[rgreeny]

I have also just purchased an 96 993. The same code showed up. It was wear in the valve guides which caused the code. I have the top end redone and it is fixed. It now passes emisions. You need to have a Porsche mechanic hook up there OBO 2 reader to get a correct reading.

[Don Plumley]

My reference shows P1117 as "O2 Sensor Heating"

I had similar O2 sensor codes when I first got my 96 IIRC. I used the Bosch generic 4 wire kit with their handy in-line splice adapter to use the factory harness. Pretty easy DIY.

Given the alternatives, for the $100 for the sensor, I'd give it a try, clear the code with your scanner, then drive around a bit to set the readiness codes.

Porsche 993 DTC's:

P1102 Oxygen Sensor Heating
P1105 Oxygen Sensor Heating
P1107 Oxygen Sensor Heating
P1110 Oxygen Sensor Heating
P1115 Oxygen Sensor Heating
P1117 Oxygen Sensor Heating
P1119 Oxygen Sensor Heating
P1121 Oxygen Sensor Heating
P1123 Oxygen Sensor Heating
P1124 Oxygen Sensing
P1125 Oxygen Sensing
P1128 Oxygen Sensing
P1127 Oxygen Sensing
P1128 Oxygen Sensing
P1129 Oxygen Sensing
P1130 Oxygen Sensing
P1136 Oxygen Sensing
P1137 Oxygen Sensing
P1138 Oxygen Sensing
P1139 Oxygen Sensing
P1140 Load Signal
P1157 Engine Compartment Temperature
P1158 Engine Compartment Temperature
P1213 Fuel Injector Cylinder 1
P1214 Fuel Injector Cylinder 2
P1215 Fuel Injector Cylinder 3
P1216 Fuel Injector Cylinder 4
P1217 Fuel Injector Cylinder 5
P1218 Fuel Injector Cylinder 6
P1225 Fuel Injector Cylinder 1
P1226 Fuel Injector Cylinder 2
P1227 Fuel Injector Cylinder 3
P1228 Fuel Injector Cylinder 4
P1229 Fuel Injector Cylinder 5
P1230 Fuel Injector Cylinder 6
P1237 Fuel Injector Cylinder 1
P1238 Fuel Injector Cylinder 2
P1239 Fuel Injector Cylinder 3
P1240 Fuel injector Cylinder 4
P1241 Fuel Injector Cylinder 5
P1242 Fuel Injector Cylinder 6
P1265 Airbag Signal
P1275 Oxygen Sensor Aging Ahead of Three Way Catalytic Converter
P1276 Oxygen Sensor Aging Ahead of Three Way Catalytic Converter
P1313 Misfire Cylinder 1 Emission Related
P1314 Misfire Cylinder 2 Emission Related
P1315 Misfire Cylinder 3 Emission Related
P1316 Misfire Cylinder 4 Emission Related
P1317 Misfire Cylinders Emission Related
P1318 Misfire Cylinder 6 Emission Related
P1319 Misfire Emission Related
P1324 Timing Chain out of Position Bank 2
P1340 Timing Chain out of Position Bank 1
P1384 Knock Sensor 1
P1385 Knock Sensor 2
P1386 Knock Control Test Pulse
P1397 Camshaft Position Sensor 2
P1411 Secondary Air Injection System
P1455 A/C Compressor Control
P1456 A/C Compressor Control
P1457 A/C Compressor Control
P1458 A/C Compressor Signal
P1501 Fuel Pump Relay End-Stage
P1502 Fuel Pump Relay End-Stage
P1510 Idle Air Control Valve
P1513 Idle Air Control Valve
P1514 Idle Control Valve
P1515 Intake Manifold Resonance Flap
P1516 Intake Manifold Resonance Flap
P1524 Camshaft Adjustment Bank 2
P1530 Camshaft Adjustment Bank 1
P1531 Camshaft Adjustment Bank]
P1539 Camshaft Adjustment Bank 2
P1541 Fuel Pump Relay End-Stage
P1551 Idle Air Control Valve
P1552 Idle Air Control Valve
P1553 Idle Air Control Valve
P1555 Charge Pressure Characteristics
P1556 Charge Deviations
P1557 Charge Deviations
P1570 Immobilizer
P1571 Immobilizer
P1585 Misfire With Empty Fuel Tank
P1593 Intake Manifold Length Tuning 2
P1594 Intake Manifold Length Tuning 2
P1595 Intake Manifold Length Tuning 2
P1600 Voltage Supply
P1601 Voltage Supply
P1602 Voltage Supply
P1610 MIL Activated Externally
P1611 MIL Activated Externally
P1614 MIL Activated Externally
P1640 Engine Control Module
P1656 Coolant Shutoff Valve
P1671 Engine Compartment Purge Fan End-Stage
P1673 Fan End-Stage
P1689 Engine Control Module
P1691 Malfunction Indicator Lamp
P1692 Malfunction Indicator Lamp
P1693 Malfunction Indicator Lamp
P1704 Kickdown Switch
P1710 Speed Signal Right Front
P1715 Speed Signal Left Front
P1744 Manual Program Switch
P1746 Control Unit Detective (Relay)
P1748 Control unit defective (Relay sticks)
P1749 Version coding
P1750 Voltage Supply Solenoid Valve Pressure Regulators 1
P1761 Shiftlock P/N
P1762 Shiftlock P/N
P1764 Instrument cluster triggering
P1765 Throttle-valve information error
P1770 Load signal from ECM
P1782 Engine Engagement
P1813 Pressure regulator 1
P1818 Pressure regulator 2
P1823 Pressure regulator 3
P1828 Pressure regulator 4

[Don Plumley]

This is a bit more detailed so you can isolate the specific sensor:

P0130 O2 sensor circuit (Bank 1 sensor 1)
P0131 O2 sensor circuit low voltage (Bank1 sensor 1)
P0132 O2 sensor circuit high voltage (Bank 1 sensor 1)
P0133 O2 sensor circuit slow response (Bank 1 sensor 1)
P0134 O2 sensor circuit no activity detected (Bank 1 sensor 1)
P0135 O2 sensor heater circuit (Bank 1 sensor 1)
P0136 O2 sensor circuit malfunction (Bank 1 sensor 2)
P0137 O2 sensor circuit low voltage (Bank1 sensor 2)
P0138 O2 sensor circuit high voltage (Bank 1 sensor 2)
P0139 O2 sensor circuit slow response (Bank 1 sensor 2)
P0140 O2 sensor circuit no activity detected (Bank 1 sensor 2)
P0141 O2 sensor heater circuit (Bank 1 sensor 2)
P0142 O2 sensor circuit malfunction (Bank 1 sensor 3)
P0143 O2 sensor circuit low voltage (Bank1 sensor 3)
P0144 O2 sensor circuit high voltage (Bank 1 sensor 3)
P0145 O2 sensor circuit slow response (Bank 1 sensor 3)
P0146 O2 sensor circuit no activity detected (Bank 1 sensor 3)
P0147 O2 sensor heater circuit (Bank 1 sensor 3)
P0148 Fuel delivery error
P0149 Fuel timing error
P0150 O2 sensor circuit (Bank 2 sensor 1)
P0151 O2 sensor circuit low voltage (Bank 2 sensor 1)
P0152 O2 sensor circuit high voltage (Bank 2 sensor 1)
P0153 O2 sensor circuit slow response (Bank 2 sensor 1)
P0154 O2 sensor circuit no activity detected (Bank 2 sensor 1)
P0155 O2 sensor heater circuit (Bank 2 sensor 2)
P0156 O2 sensor circuit malfunction (Bank 2 sensor 2)
P0157 O2 sensor circuit low voltage (Bank 2 sensor 1)
P0158 O2 sensor circuit high voltage (Bank 2 sensor 1)
P0159 O2 sensor circuit slow response (Bank 2 sensor 1)
P0160 O2 sensor circuit no activity detected (Bank 2 sensor 1)

[craig722]

I ran your code on my Actron CD that comes with their Pocket Scanner. Your code came out as "Manufacturer Control Fuel Air Metering" for what that's worth.

I thought the scanner only worked on domestic cars when I bought it, but the CD includes DTC's from most of the big foreign car manufacturers, as well. I'll post back if I find anything more on a fix.

[Don Plumley]

The code from the scanner is accurate. The description of the code fault is very often wrong in the scanner or in their generic reference guides. The list I posted above is from the Porsche Factory manual.

[JAD1957]

I have a 95 993 that Ive had since new and had a cel come on and think it may be one or both o2 sensors. Can anybody tell me where the o2 seneors are located. Im wanting to go ahead and replace both of them, thanks, John @ johnsebolt@comcast.net