check engine light and o2 sensors

[100deltacharlie]

Greetings
I have a 2003 boxter s. It started to over heat and the check engine light came on. Shop put in new thermostat that cured overheat prob. He said code for o2 sensor flashed. He reset comp and we drove a couple of trips( 100 miles or so) check engine light came on so he recommended 2 front o2 sensors.
1. Is this common at <35,000 miles
2. What is a fair price to replace..his estimate seems high.
Thanks
David772 486 3899

[antny]

Replacing the two front O2 sensors is an easy job. The part is not cheap. I think I paid 218 bucks ish for an O2 sensor not too long ago.

[Timco]

Aren't Bosch O2 sensors like $60-80 at Napa??

[Chuck W.]

Sunset Porsche has OEM ones;

OXYGEN SENSOR, LEFT
Part Number: 986-606-127-01
$227.61

OXYGEN SENSOR, RIGHT
Part Number: 986-606-128-01
$235.53

Subtotal Amount: $463.14

EXHAUST COMPONENTS for 2003 Porsche Boxster

[jdraupp]

Dont get the ones with the porsche sticker on the box. Bosch is the oem manufacturer. The key in diagnosing this is looking at your resistance numbers. If your mechanic is going off code alone you may be changing something that doesn't need changing. This often gets misdiagnosed when in reality its your maf that is bad.

[jklaspok]

Pelican Parts has them at a reasonable price.
1999 Porsche Boxster Base Convertible - Exhaust Pipes, Manifolds & EGR - Page 1

[Iverman]

check out FCP Euro. O2 sensors from $86
https://www.fcpeuro.com/Porsche-parts/Boxster?year=2001&e=41&m=87&keywords=Oxygen%20Sensor

[Topless]

Originally Posted by 100deltacharlie

Greetings
I have a 2003 boxter s. It started to over heat and the check engine light came on. Shop put in new thermostat that cured overheat prob. He said code for o2 sensor flashed. He reset comp and we drove a couple of trips( 100 miles or so) check engine light came on so he recommended 2 front o2 sensors.
1. Is this common at <35,000 miles
2. What is a fair price to replace..his estimate seems high.
Thanks
David772 486 3899

Very unusual to need new sensors at 35k miles. Get the actual codes and report back here. Often the O2 sensors are simply reporting a problem upstream so don't kill the messenger yet.

[Stevetwood]

So I recently had a P1128 and P1130 codes (O2 sensors left and right). I would clear them and they returned every 100 miles or so. I bought a $15 code reader from Amazon just to read and clear the codes
I followed the instructions on this site, bought some $11 MAF cleaner from Amazon, removed theMass Airflow Sensor (MAF) and gave it a good clean with the MAF cleaner spray in the right areas for a couple of minutes. I then got a P1128 code with a P1130 pending.
I swapped the loose fitting dirty OEM air filter for a new Porsche one which proved a firm sealed fit in the air filter tray and sprayed the MAF sensor again with the cleaner and after 800 miles the CEL light has stayed off. My engine has done 77k miles and they are probably the same O2 sensors since new.

[bobbeck]

Just replaced both front O2 sensors. Bosch sensors were $80 each online. My car threw the O2 sensor codes, randomly misfired and got horrible mileage. 1500 miles later all is fine.

[CrisZenithBlue]

Originally Posted by Stevetwood

So I recently had a P1128 and P1130 codes (O2 sensors left and right). I would clear them and they returned every 100 miles or so. I bought a $15 code reader from Amazon just to read and clear the codes
I followed the instructions on this site, bought some $11 MAF cleaner from Amazon, removed theMass Airflow Sensor (MAF) and gave it a good clean with the MAF cleaner spray in the right areas for a couple of minutes. I then got a P1128 code with a P1130 pending.
I swapped the loose fitting dirty OEM air filter for a new Porsche one which proved a firm sealed fit in the air filter tray and sprayed the MAF sensor again with the cleaner and after 800 miles the CEL light has stayed off. My engine has done 77k miles and they are probably the same O2 sensors since new.

i have exactly the same problem for a few weeks now but the car is running fine.
i am suspecting a vacuum leak because my MAF is a few months old (still sprayed it twice) and the air filter as well and its a tight fit.

was your car running fine with the CEL on?

[Stevetwood]

@CrisZenithBlue When the CEL light was on, the car was running okay (ish) although the fuel economy was very poor, at about 23 mpg on Shell 98 RON fuel (No ethanol). Now the fuel economy is 28-30 mpg on the same fuel and my son has taken the car to France this week an told me yesterday getting an average 36 mpg driving at around 80 mph (with the customary toll-booth drag race at each booth) for over 180 miles on their freeways. The car has done nearly 3,000 miles now and the CEL has stayed off. So now working the problem in my head (beware, these could be the ramblings of an idiot), I think that the MAF was dirty and needed cleaning because the previous owner allowed the mechanic to replace the air filter with a poor fitting non-Porsche air filter that allowed dirty air to enter the system which soiled the MAF sensors which was unable to measure the correct quantity of air value (I cleaned the MAF twice and had a P1128 value and a pending P1130 value between the two cleans which I cleared down, then I fitted the new Porsche air filter when I cleaned the MAF for the second time). The O2 sensors were reading a high O2 value because of the air filter vacuum leak causing the ECU to squirt more fuel into the system leading to poor fuel economy.

@100deltacharlie - as was said here earlier by @Burg Boxster O2 sensors don't tend to go in pairs and throwing a couple of hundred $ at replacing them is not always the answer. A good mechanic will try to work the problem and not just change the suggested faulty parts. I got the code reader from Amazon search for "U480 CAN-Bus OBDII OBD2 EOBD Trouble Code Read Diagnose Tester Diagnostic Scanner" and it was closer to $25 with postage.

[mikefocke]

What is the exact code that the mechanic read? P???? is the format.

If it does point to an O2 sensor, you or any muffler shop can replace it. Takes 15 minutes and most of that is waiting for the exhaust system to cool down.

Bosch makes em for Porsche to label. I used them. Get the ones where the pigtails are crimped on at the factory. Not soldered on and you can't do as good a job of crimping.

Do not use "universal" or off-brand parts. Too many problems reported.

Bosch part numbers are in this posting http://sites.google.com/site/mikefocke2/oxygensensors though the parts sources and prices are surely out of date.

[100deltacharlie]

Thanks for all of he input. I do not have the exact codes. My local independent parts store has them for $100 ea. Napa is probably less. A video I saw shows coming through the wheel wells to access. Is this the best route? If so I will probably do it myself.
What kind of code reader did you get for $15?

[Burg Boxster]

O2 sensor CEL codes only mean value being reported back by the sensors is not in correct range. Period. End of Story.

Issue COULD be A sensor, though rarely does more than one sensor go bad at same time let alone on opposite banks (unless fouled by something further upstream). You start by checking the wiring to the sensor and then testing sensor itself w/ a multimeter. Proceed from there but otherwise blindly throwing a couple hundred $ at the sensors is frankly plain foolish.

Good luck

PS - Most natl auto parts stores/chains will read codes for free

[100deltacharlie]

Leaving town for a few days..digging into this one when i get back...thanks to all

[100deltacharlie]

Got back into the problem and related a problem with my boat fuel(not the same fuel). Switched to only Mobil premium instead of just any premium. The check engine light is now off. I wonder if it is an ethanol issue?

[jontalk]

My car just turned 80K. Both front sensors were replaced at around 72K miles with the Bosch OEM parts purchased from ******************************** AZ for around $100 or so each. In the past year or more, the CEL light throws the code saying the driver side sensor is aging. The shop during the oil service swapped the sensors and last night the CEL light came on again. This seems very odd since the Bosch part description states they're normally replaced every 100K miles, so why would the engine computer keep throwing the codes with O2 sensors that barely have 8K miles on them?