Ponchobroke

I get an intermittent CEL often over the last couple of years (now more often) that happens when I am tooling around town at lower speeds and rpm. As I increase the rpm and "push" the gearing the light goes away only to return while setting at a light for an extended time ( I can actually make the light go off by reving the engine). It does not affect my ability to get smog clearance here in Oregon but it is getting annoying. Has anyone experienced this.. I was thinking possible O2 sensor.

Otherwise it drives as expected for 150K mi.

thanks in advance,

whatyoutalknaboutwillis

Yep--O2 Sensor. Replace it and it will go away. Same thing with my 95. I went with an aftermarket that came with a universal wire couple. Very easy and saved a significant ammount of money over a factory replacement.

bart1

I don't know if it works on 993s, but you can dothe "blink test" on my 968, which will tell you the last code that was thrown. Never tried it on my 9933 and never have had a CEL on it.

bart1

Here is the procedure and codes for 968s, if you want to give it a shot:

Reading Porsche 968 Fault Code with Check-Engine Lamp (not for R.O.W. cars)

Basic Procedure:
1. Verify operation of Check-Engine lamp. (Lamp should light up when ignition is switched on)

2. Fault codes on USA vehicles may be read using the Check-Engine lamp. To trigger the flashing code, fully depress the accelerator pedal for 3 seconds with the engine off and the ignition on until the Check-Engine lamp flashes. Then ease off the throttle.

3. Light will repeatedly flash stored code sequence(s) until ignition is turned off.

Known Limitations:
Diagnostics of this nature are typically performed by professionals with access to specialized tools. The Bosch Hammer/System Tester 9288 (or one of it's successors) is the preferred way to read fault codes and will be required to erase the fault memory. Also, the fault codes listed are intended to serve as a starting point for follow-on diagnostic efforts and, thus, knowing the fault code is not necessarily the same as knowing which component is faulty.

NOTE: A "2" IN THE SECOND DIGIT LOCATION OF THE 4 DIGIT CODE INDICATES AN "INTERMITTENT" ISSUE

Fault Codes (968): (Flashing Code Fault Description)
1-5 No Fault
1-1-1-1 Supply voltage
1-1-1-4 Engine temperature sensor 2
1-1-1-6 Throttle potentiometer
1-1-1-7 Oil temperature sensor
1-1-1-8 Rpm signal
1-1-1-9 Speed signal - Speedometer
1-1-2-1 Air flow sensor
1-1-2-3 Oxygen regulation
1-1-2-4 Oxygen sensor
1-1-2-6 Ignition timing change
1-1-2-7 Open winding of idle stabilizer
1-1-2-8 Close winding of idle stabilizer
1-1-2-9 Activation of AC relay
1-1-3-1 Knock sensor 1
1-1-3-2 Knock sensor 2
1-1-3-3 Control unit faulty
1-1-3-4 Hall signal
1-1-3-5 VarioCam
1-1-3-6 Idle CO potentiometer
1-1-4-1 Control unit faulty
1-1-4-2 Fuel pump relay (DME-relay)
1-1-4-3 Tank ventilation relay
1-1-4-5 Check Engine warning lamp
1-1-5-1 Injection valve cylinder 1
1-1-5-2 Injection valve cylinder 2
1-1-5-3 Injection valve cylinder 3
1-1-5-4 Injection valve cylinder 4

*Second number in sequence may vary (1 is for a constant fault. 2 is for a loose contact)

993Maineiac

These have been posted here before. A search should find them quickly.

stace

it was the same for me - O2 sensor for sure. easy DIY

AOW162435

What's a 9933?

Oh, I see:





Andreas

bart1

Suck it, mr clean!

Ponchobroke

To all... thanks for the confirmation...we rock!!!