and so the trouble starts.......
 

hsve had my 99 boxster 2 weeks and CEL has come on. dealer knew as after 20 miles from pick up it came on and I brought it back. they cleared it and said when.they filled my tank.they may have left csr running and gave a false o2 sensor read. well it csme back 3 days later. autozone read it and it was a p1128 with a p1123 pending. i bought a reader, cleared it, and came back twice now as p1128, p1130 pending. it drives fine i think, but always scared when CEL light is on I do notice when in triptonic automatic mode seems sluggish between 2-3 gears, isnt that way in manual triptonic. also when in 5th and I gun it, it doesnt accelerate fast and will drop down to 3rd gear then climb back up. very noticeable jerk dropping back to 3rd as u can imagine. is this normal or because of CEL codes?

thoughts of what i need to do? dealr wont do anything.

NPR

Maybe it needs the MAF to be cleaned, maybe all four O2 sensors need to be replace, maybe the MAF needs to be replaced. It is a 99. Not the the newest and these things are expected and are just part of the general upkeep of a boxster. Work out all the kinks and enjoy the car. If you put the effort into it, it will reward you.

J

If you purchased it from a dealer, what is your warranty? Many dealers give a limited 30,60 or 90 day full or 50/50 warranty. If it happened within 20 miles of purchasing, I would have taken it back and not spent any money on a reader or anything else until they took care of the issue.

Many states have a 24,48 or 72 hour period that a consumer product can be returned if it is not working properly. Check there also. Also the codes mean nothing to me but since it happened upon leaving the dealership, check your caps (gas, oil...) and make sure everything is tight. Maybe they left something loose.

no.warranty. I did bring back and they basically just cleared the code. not happy,with that dealership anymore. all seals are tight. thinking about popping engine cover pr some online instructions and cleaning MAF. Code came back a few days later and keeps coming back, I.think.they knew when they sold it and cleared it.I wont trust them for service now either and dont get me started in mystery $1000 that showed up on my ccard w/o authorization that they refused to credit until I threatened them.with action.6 news. do my symptoms sound like MAF issue? how do I get to O2 sensors? thx

Do clean the MAF carefully. If that fixes the problem, you're good for a while.

The problem with the Porsche diagnostic tool is that it gets confused easily and it's expensive to isolate problems. If one of your O2 sensors is faulty, it can register that the MAF or other O2 sensors are faulty and that's not accurate.

With an 11 year old car that probably hasn't had the MAF or O2 sensors replaced, you're probably in need of all five parts. Just don't buy Bosch factory seconds off eBay... they're cheap for a reason. Best place to get parts for our cars cheaper than your local stealership is Sunset Imports in Oregon. They sell at 10% over hard cost plus shipping.

Sounds like either a bad MAF or intake air leak. A common problem on a 12 yr old car and usually a cheap fix. Because both banks of O2 sensors are reporting the same thing it is unlikely failed O2 sensors. Here is more discussion on this:
P1123, P1128 CEL Codes - RennTech.org Forums

Any time I ever had those types of codes in the past it turned out to be the MAF. Get the special MAF cleaning spray and clean that sucker! You'll also be impressed how much better the car will run with a good MAF sensor.

you folks have been great. do my.symptoms.sound like MAF, or what are hour thoughts on.that?

ok, so read codes this morning, now says p1123 with pending, p0154, p1128, p1130. still sound like dirty MAF? am I ok to.drive to my brothers party today? 250 miles r/t thx folks

Somebody (who knows more about Boxster upkeep than I) may chime in here, but my understanding is that, as long as it is not a flashing CEL, the car is safely driveable.

I had similar codes on my 97 after changing my air filter over to a K&N. I ended up removing the K&N air filter, cleaning the MAF and the codes cleared. I now have over 2000 miles of driving with no CEL's. As for driving that far with an "issue", I don't know that I would do it. Of course it only took me 20 minutes to clean the MAF, if you have the time give it a try.

Check your Air Oil Separator (AOS). While the motor is running (and warmed-up) remove the oil fill cap... Is the cap hard to remove? Does the oil fill tube sound like a shop vac and the motor almost die? If you have these symptoms then the AOS is bad. If you remove the oil fill cap and the the motor RPM's stay the same or increase a little then AOS is probably OK.

P0154

Oxygen Sensor Ahead of Catalytic Converter (Cylinders 4 - 6) - Interruption of Signal

This sounds like a bad sensor, bad connection, or rodent chewed sensor wiring. Check your O2 sensors. If they are OEM Bosch and your connections are tight, look for damaged wiring. The car is probably safe to drive if your CEL is not flashing but get it sorted soon. It is running on default mixture settings which look like they are too lean. Running for a long time like this may damage your motor or cats.

Possible bad MAF, bad AOS, intake air leak, O2 sensor wiring... time to dig in and apply the process of elimination.

I went through a very similar situation when I bought my 2000 S Boxster last winter. After about a month I got a 1128 CEL. I cleared it and it came back within a week.

You could have a bad MAF but you should get a smoke test done before you jump to conclusions. Check around to find a shop that has a smoke test machine for locating vacuum leaks. It doesn't have to be a Porsche shop but they need to know enough about Porsches to gain access to the motor. The test should cost around $100. Smoke is pressurized into the intake manifold and the tech can easily locate any vacuum leaks because the smoke will be blowing out of the motor wherever a leak is. If you don't have any leaks chances are it's a bad MAF but you need to fix the leaks first if there are any. In the case of my car the oil fill tube leaked and also the brake booster pipe.

Fix the leaks and drive the car. If the CEL comes back and it's the same codes buy a new genuine MAF. It's easy to put in. My MAF cost about $275. On my car after I fixed the oil fill pipe I still got the CEL and put in a MAF. It seemed to totally fix the problem and I never got the CEL again. Later during the hot summertime I could hear some hissing. Hissing is a good clue that you have a vacuum leak. It turned out to be the vacuum pipe for the brake booster (which I hadn't fixed yet) and after that got fixed the car has never driven better. It's really worth it to get it fixed right.

You might want to buy a Durametric scan unit. They cost about $300 and are pretty handy. Besides reading and clearing codes they let you see the data values from the sensors. That's how I knew I had really fixed mine when I put in the new MAF because the fuel adaptation numbers went from way off to almost perfect.

ok,dove on and opened up engine area. changed air filter n cleaned maf. drove first with maf out n did notice difference. cleaned maf n put back in, got CEL after 4 miles. so I will
order new maf tomorrow n see if that fixes issue.

npr

ok, so funny thing. drove around corner today, CEL still on, ran into store, turned car on again, CEL was off? is this normal after cleaning that it would come on again, but then go off? maybe took a while to run thru system? puzzled but glad light is off but for how long. car running same as pre-cleaning, seemed better when had MAF out.

npr

I had 1128 and 1130 and finally fixed it with a new OEM gas cao. I had a leak at one point which was fixed but it kept happening. Ended up being a junk autozone gas cap.

Same codes, drove me nuts. cleaned maf no change. had been using mid-grade non-ethanol from our neighborhood marina. Changed to hi-test, added B-12 gas conditioner and no more light for 600 miles.

NPR, what are the Florida laws on purchase? Here in NY any dealer used or not is subject to lemon laws, I would think these people would be compelled to fix the problem, perhaps consider contacting the Florida attorney general as well.