Hi all, I recently purchased a 2002 Boxster S and am afraid I may have gotten more than I had bargained for.

On the drive home the CEL came on, and got P1128 and P1130 codes on a reader. As a first step I decided to change the air filter. Well it was absolutely disgusting. The foam on top was beginning to disintegrate and it was full of leaves, among other debris. Changed it out, and while I was there decided to have a look at the mass air flow sensor (as I've read that it often is the root cause of P1128 and P1130). Well, this is what it looked like. The plastic seemed mostly clean, however the rubber gasket on the back side of the sensor is in terrible shape. It's terribly sticky and it comes off on my hands.

So is it worth me to clean it with MAF cleaner, or just purchase a new one?

I've performed some searches and haven't found this exact issue.

This forum is terribly useful. Thanks in advance for any input you have.


Gross!

 

You've got nothing to lose by trying to clean it. Use only the proper spray, CRC makes a product designed for MAF's, and do not touch the sensor wires. Let it air dry. I did mine a few years ago and did the trick. Eliminated a slightly fluctuating idle but I had no codes.

 

Do the above advice & buy a new Bosch MAF sensor. after you reinstall the cleaned MAF drive the car 30 minutes to check improvement.
Next install the new Maf & test drive again. If no improvemnet over the old MAF and it runs well with the old MAF, just reinstall the original MAF & keep troubleshooting.
Keep the new MAF you will need it sometime & it's helpfull for troubleshooting.

 

If your air filter was nasty, you should check the front inlets (radiator) for leaves too. Early on I was told that you can tell how a car was cared for by inspecting these for leaves and debris. A shop vac does the trick.

 

And what do you suppose the throttle body looks like? Or the oil?

 

So the plan is to change to a new MAF sensor, and keep and clean the old one in case there's a need for it in the future. Once it comes in I'll clean the whole intake from exterior inlets to throttle body. I have some CRC TB cleaner I plan on using for the TB, and CRC MAF cleaner for the MAF. Any tips on removing the throttle body? I've read several users busting their coolant lines while removing it...

 

Okay, MAF came in, installed, and before I cleared out the codes decided to tidy up the throttle body. It had a fair amount of deposits on it. Thats all cleaned up now. However, there is some oil in the Intake Plenum/manifold. Is this from a failed Air/Oil Seperator?

If so, is it safe to put the car back together and run it until the new AOS comes in?

For what its worth, there was no white smoke from the exhaust...However the whole engine bay smelled of oil.

 

After changing the MAF, cleaning all the oil I could find in the intake, I buttoned everything back together and cleared the codes. After starting the engine I verified all the codes were gone and went for a drive around the neighborhood. No CEL, engine performed fine. When I pulled back into the driveway I checked and there were no logged codes, however P0302 was a pending code. Is it safe to drive as is?

 

Oil in the Plenum is an indication of a failed AOS.
Use a Manometer to test the AOS.
They’re simple to make.

Here’s mine:



Manometer from Amazon, some vacuum line, a Porsche oil cap, a small fitting, and a little silicone to help seal it.

 

Ironically while I'm in line to get an inspection sticker the AOS must have failed. Plumes of smoke filled the shop, smelling of oil. I got home and there was a film of oil throughout the intake. Cleaned it out again, installed a new Porsche AOS, cleared the codes, and all is well again (I hope).

While taking the old AOS off, the lower tube connecting it to the crankcase looked like the attachment. Should I be concerned about coolant getting into the oil (i.e. cracked head/failed gasket) or has anyone else experienced this while changing their AOS. I ran it for over an hour this weekend with no codes, and the temp stayed at 180 the entire time.