99 Boxster Check engine light issue ( Not Normal)

[Topless]

Yep,
You can spend a lot of money and change a lot of parts but not fix the problem on these cars. The money pit can get real deep, real fast.

A careful diagnosis starts with the symptoms, exact error codes, model, year, mileage, and any recent work done. Get your own code reader and pull the codes, write them down and report back here. Then we can walk you through the process. There are a lot of common problems and easy fixes but you will need the codes first.

[porscherescuer]

Thanks for the responses guys. I will get the exact codes tonight. I know it was for the 02 sensors. One code for each sensor. My mechanic replaced all of them and it threw the exact same codes the next time I drove it. I have tomorrow off and would love to get to the bottom of this tonight and tomorrow. I will get a scanner and post the codes asap. Keep in mind that my mechanic is a Porsche repair specialist and has the very expensive computer to hook up. So, I'm sure his codes are correct and will be much more accurate than what I can get.

[JFP in PA]

Just as a reference point, you should get the exact same codes with a $40 code reader that a shop with a $17,000 a year PIWIS gets; only difference is what is done with that information. Diagnostics is more than reading codes, it is interpreting them.

In all the years I’ve been turning wrenches, I have never seen all four O2 sensors on a car crap out at one time; never………..

[Topless]

Originally Posted by JFP in PA

Just as a reference point, you should get the exact same codes with a $40 code reader that a shop with a $17,000 a year PIWIS gets; only difference is what is done with that information. Diagnostics is more than reading codes, it is interpreting them.

In all the years I’ve been turning wrenches, I have never seen all four O2 sensors on a car crap out at one time; never………..

Yep,
If all four O2 sensors are barking they are just trying to tell me something. All going bad on the same day never happens so... What are they saying?

[stateofidleness]

a lot of times it's something happening upstream of the sensors that is causing the sensor to get bad readings. The fact that it's getting readings and reporting the inconsistency is proof that the o2 is working properly.

I, too, have never seen all of them fail at one time...

I only got one "my bad" of taking car straight to Indy without letting the board take a peek at my codes first.

Any time something "isn't right" with my car now, it's "to the boards!"

Mechanics (and often the chevy/ford guys for some reason) seem to want to throw o2 sensors at every engine problem... i dunno why.. but it's annoying.

[porscherescuer]

Thanks for the replies everyone. I talked with my mechanic today and he said the codes were for the heater circuit for all 02 sensors. I can get exact codes tomorrow, but that should give us something to go on. The first place he said to check would be the heater circuit. What is he referring to? My bet is there is a short somewhere.

[porscherescuer]

I got an obdII and the two codes it is showing are p1117 and p1121. I know these are the same codes it had before we replaced the o2 sensors.

P1117 Oxygen Sensor Heating 1 After Catalytic Converter - Below Lower Limit
P1121 Oxygen Sensor Heating 2 After Catalytic Converter - Below Lower Limit

I ordered a new o2 heater circuit relay since it was only $10. Any ideas?