engine stutter at 3000rpm, O2 sensor?

[xavier405]

Hey all, thanks for being out there to hear my question. I got a 2002 Boxster Tiptronic, 33kmi.

Two weeks ago:
CEL came on, got a code P1130: "Oxygen Sensor Adaptation Idle Bank #2". After a few days of driving with no problems, the engine got all messed up and sputtered and coughed with anything above 2000rpm. Man it was bad! I reset the engine (off then on) and the problems stopped and it was okay to cruise back to the dealer. The repair was a replaced MAF sensor. Finally, the car was back working okay!

Today:
I notice an engine stutter when going through 3000rpm in 3rd gear.
1st gear - zips right up to redline no problem
2nd gear - no problem
3rd gear - from low rpm moves up to 3k, there it shakes a bit, and accels past up to 4 and 5 and up okay. I hit this engine stutter also when : I'm driving at speed, and I mash the pedal for a downshift to 3rd and again when it goes through 3krpm it stutters for a sec.

I also tried keeping it in gear and holding it at 3krpm and of course it stutters for as long as I hold it there, it coughs and lurches.

So it sounds to me like the O2 sensor fix did not completely solve the problem here. I see in other threads that there are 4 O2 sensors and a Mass Air Flow sensor. What is their relationship? Should they all have been replaced at once? I'm heading back to the dealer for more repairs... but I want to understand whats up here...

Thanks
- Xavier

[Brucelee]

Yes there are multiple O2 sensors and of course, more than one could have gone bad. The MAF sensor can also go bad and any or all of these sensors can generate a code and the problems you are having.

I know of no way to diagnose your issue short of having the new codes that your engine is generating right now!

Good luck.

[xavier405]

I just made a correctin in my initial post - the repair was a new MAF sensor. And so now the problem is back... and this morning the CEL came on. I'll take 'er in to the shop and let you guys know what is up.

[KRZTACO]

Do you take it to the dealer?

You can also goto the shop I use:

Hergeheimer Motorsports in Lake Forest

www.herg.net

It will save you a little money, not a bargain basement place.

[xavier405]

Thanks, dude, I've heard good things about that shop. I'm still under warranty for six more weeks! So I'm going to work it at the dealer. I go to Circle Porsche. They seem okay but the real test is if they can diagnose and fix this car. My work two weeks ago was free under warrantee but appears to be incomplete.

[deliriousga]

Originally Posted by xavier405

Thanks, dude, I've heard good things about that shop. I'm still under warranty for six more weeks! So I'm going to work it at the dealer. I go to Circle Porsche. They seem okay but the real test is if they can diagnose and fix this car. My work two weeks ago was free under warrantee but appears to be incomplete.

This type of thing is tough to diagnose so make sure they have the symptoms on the invoice every time you go in. It should be typed in, not handwritten. Then if they try several things up to the expiration and they don't work it will be a related problem that should still be covered even though the warranty expires.

[KRZTACO]

Originally Posted by deliriousga

This type of thing is tough to diagnose so make sure they have the symptoms on the invoice every time you go in. It should be typed in, not handwritten. Then if they try several things up to the expiration and they don't work it will be a related problem that should still be covered even though the warranty expires.

GOOD CALL.

KRZ

[xavier405]

Well so I took the car back to the shop. It still had the engine stutter that we thought got fixed two weeks ago.

The CEL had several fault codes all having to do with the air flow and O2 sensors, and the service department still couldn't diagnose the problem. After three or four days in the shop, they discovered the problem:

The Mass Air Flow sensor that they put in two weeks ago (a new part) had failed. Seems to be very odd, that a new part out of the box would not work. So they replaced that and now the car is running fine.

CHAPTER 2
About an hour after I got my car back, last Friday night, I realized that there was a scratch in the plastic rear window! (Shoulda done a walk around!) but I called the service right then and left a message of the problem. Long story short, we have talked a lot about it over the past week and they agreed to replace the convertible top. As the service manager looked over the car, I could tell the look of dread in his face... he knew that there is no fix for the window except for replacing the top.

So off we go, back to the shop!!! Agh!!

[RandallNeighbour]

I know your multiple dealer visits are frustrating, but as an owner of a boxster well out of warranty, those trips are no charge and what they're replacing as far as the MAF are concerned are $$$$.

And the scratch in the window is frustrating, but hey, you get a brand new top! That's a very nice gift that you'll enjoy for years to come.

This little sensor issue is panning out well for you dollar-wise, huh? Be happy!

In the future, if you get a CE light code that is O2 sensor related, buy four new ones from a discounted online source and have an independent mechanic replace them if you don't have a floor jack and a wrench and the hour or less it would take you to do it yourself... with your new MAF and these, you're probably going to be CE and engine stutter free for a while unless something quite odd happens to your engine.

Should another person ask me about buying an older boxster (4+ years old), I'm gonna recommend they save up and replace the MAF and all four sensors as a preventative maintenance measure sometime soon after they take possession of their car unless they have records showing this has already been done. The number of CE lights and poor performance posts on this forum surrounding these parts on aging Boxsters seems to warrant this recommendation, even though some Boxsters have 100k on them with the factory sensors working fine.

[xavier405]

Yeah, there is indeed a silver lining. this new top. And there was even an unfortunate scratch on the top fabric already, so here comes a nice clean new top!!

Sooner or later I will scan in my printout of the engine diagnostics and attach it to this thread.

Cheers
- Xavier