Tamaren

Hey, Long time no see. After selling my last Boxster, I realized my mistake and wanted another one. Found one in LA, (I'm in Arizona) so I flew in, and picked it up, and was happy to find a very clean '01 S in Orient Red Metallic and the 6 speed. IMS, good service history, 65k miles, exc, exc.

So I'm driving it the 400 miles home, and I turned down my street in Tempe and a CEL. Go figure.

Plug in Durimetrec and it's a P0430 (Bank II Cat. Converter).

Here is my question- The car has been babied, and just spent the last 400 miles idling along at 2500 RPM, Do I clear the code and run her pretty good to get her cleaned out? Italian tune up, as it were? or should I look further into it?

My plan is to clean the MAF sensor first thing anyway, I believe the previous owner had an oiled K&N (which is not great) So would that cause it?

I have the paperwork for all 4 O2 sensors being replaced about 3,000 miles ago, so I'm thinking it's not that.

Anything else it could be? Is it possibly the Cat from living in LA?

Thanks guys, It's good to be back in a Boxster.

Tamaren

Update- Went into the top end and found a very oily cone filter with no shielding and a oily tube going to the MAF. Figuring that is my problem.

If I wanted to source a factory airbox, would that be possible to re-install? not a ton of room there. Or what are my options? Ideally, I like the idea of the stock filter unit. Peace of mind, as it were.

Anker

It may also be the O2 sensors, especially the down cat one. I got that code and replacing both O2 sensors on that bank cleared the code. Inexpensive and easy to do if you get the O2 sensor removal tool from Pelican.

Quadcammer

I have a factory airbox with a nearly new filter for a good price if you're interested.

I would think that this would be a good start to correcting your problem, but its most likely an 02 sensor that is causing the problem.

Macster

Go back to the factory air box and factory air filter. Be sure there is no way for unfiltered or unmetered air to get into the engine.

I usually don't recommend this but in this case I'll make an exception and suggest you *with care!* clean the MAF. Use a residue free cleaner.

Do not scrub, probe the MAF surfaces just spray the cleaner on and let the MAF drip dry. Do this over a clean white paper towel to see what if anything comes off the MAF.

My experiencs is the drive of 400 miles -- even if "idling" at 2500 RPMs -- is sufficient to remove engine deposits and any converter deposits. There is nothing to be gained by any more hard running. IOWs, no need to for an Italian tuneup.

The SOP for a P0430/P0420 is if it is accompanied by any O2 sensor error codes replace the indicated O2 sensors then clear the codes then road test the car. If the P0430/P0420 error codes come back replace the indicated converter(s).

But get the intake sorted out first. Clean the MAF. Since the car is new to you and has a modified intake maybe the previous owner has been at the exhaust? Maybe it had an aftermarket exhaust?

Anyhow, check or have checked by your favorite highly regarded Porsche shop the exhaust system to make sure there are no exhaust leaks that everything is nice and tight.

The converters are covered by a warranty. At 65K miles the converter is still in the warranty miles limit -- which I think is 70K or 80K miles -- my point being this really is a "new" car make that "new" converter failure. Unfortunately while the converter is still within the covered miles the warranty has expired on time.

So, all you can do is get the car back to stock regarding the intake. Be sure the intake is working correctly.

Clean the MAF.

Check the exhaust system for leaks or ?

Be sure you run a top tier gasoline. If available to you where you are my advice would be to use Chevron Supreme. The Techron in the fuel made a difference and for the better in how my 2002 Boxster engine runs.

Clear the codes.

Road test the car.

If the CEL comes back on check for all active and pending codes. If any O2 codes address those. Clear the codes road test the car again. If the P0430/P0420 error code comes back that's a pretty good sign the converter is bad.

I don't know the laws in your area but you may be able to source a used converter and have it installed which should eliminate the error code. This is what I did in the case of my 2002 when I got tired of the P0430 and the noise from the converter. (The brick was loose which is why once in a while it would trigger a P0430.)

I picked out 2 matched converters off a car similar to mine. I shook both converters vigorously to make sure both had no rattles (loose converters or fragmented converters).

BTW, once I had assured myself the converters didn't rattle I handled them with extreme care. You do not want to toss these in the trunk and let them bang around and into each other.

After the "new" converters were installed the P0430 error code went away the car passed smog and has been running just fine ever since.

Well, at least in regards to the converters. The engine has been tripping the CEL with a P1128 error code which the tech suspects is a small intake leak. The car is going in for this as soon as I get my Turbo back after it gets its fuel pump replaced.

But the converters, which were installed a couple of years or more back, have nothing to do with the P1128 error code.

Schnell Gelb

For the re-install of the airbox. A little research may be wise.
The reason I say this is I have done this and there are issues that become insurmountable and difficult.
To remove the airbox you need to drop that side of the engine. Even so, most resort to cutting it into pieces to extract (Search). Now think about reinstalling it in one piece? How exactly - without completely dropping the engine at least 6 inches ? &/Or remove the 4-5-6 intake manifold.
Search for a U.K. video where they replace a 996 airbox with a 997.Very few practical details supplied ! The 997 is slightly larger/better flowing but is worth the trouble(?)
The other alternative is to fab your own filter housing withing the fender space. A few others have done this.(Search)
If you decide to drop the engine 6" ask about a while-you-are-in-there list.
While you evaluate options maybe use a new,dry K&N-type filter. That will give you time to solve the Code problem.
If you do a Smog Test on a newly purchased car (in Calif) and it Fails(yours would on multiple issues) , it is the Sellers finacial responsibility to pay for all the rectification required to get the equipment returned to ARB approved parts and pass the Test. That may run to 4 figure$ for your situation.
O2 sensors - check the part number very carefully against the OEM #Some of the Interchange Lists are wrong. Publish your #s here so we can confirm.
Also check for "Readiness Staus Codes" -you may have an SAI issue.

AnthonyGS

In other brands many have had good luck using crc electric contact cleaner to clean MAF wires. Spray on let evaporate. Touch nothing.

Macster

If you do a Smog Test on a newly purchased car (in Calif) and it Fails(yours would on multiple issues) , it is the Sellers finacial responsibility to pay for all the rectification required to get the equipment returned to ARB approved parts and pass the Test. That may run to 4 figure$ for your situation.

That's a good point and before the OP really tackles getting this car sorted he should take any advantage he can of the CARB rules/regulations to put the burden of getting the car sorted out on the seller.

Schnell Gelb

Agreed - in Ca at least, once the new owner starts diy 'rectification' ,it gets murky
Usually the ( ignorant but honorable) Seller just buys it back. The legal fees, penalties, Referee, parts and labor costs would far exceed the price of the car.

Tamaren

Sorry I haven't replied sooner, Going to try and address all of the very helpful comments. Thank you all for the help.

The previous owner did all 4 O2 Sensors about a year (3,000 miles) ago. It would be very odd for them to fail again I figure.

Was able to get the intake sorted out and took everything up to and including the throttle body off and cleaned everything. Like I said, Oil residue was present so I made sure to clean everything after the installation of the new filter. I was able to source the factory intake, but after reading up on the installation I decided against it and fabricated my own with a dry filter. I've put 50 miles of varied driving back on the car and am planning on running a drive cycle, because I do have to pass smog here. As long as everything looks good with the drive cycle, I am getting fine readings from the o2 sensors when I'm monitoring them driving today. I'm thinking I got lucky and it was a dirty MAF.

Had good luck with Chevron gas, so that is what I run as well. In the summer it gets hot enough down here we can't run Ethanol in the fuel, so we get straight gas and the Porsches really like that.

I'm not going to put that on the seller, I bought the car as is, where is, and I don't think it's right to go after him for something like that. The car had current registration in Cali, so it passed there, so it very well could of been something that happened on the drive back.

My car, my responsibility. I'm not going to send a 4 figure bill to someone who (probably) had no control over the situation.



Will keep everything posted, Planning on running some drive cycles tomorrow and going for Smog (just as long as the sensors go ready)

Macster

Not sure "as is where is" applies in the case of CARB compliance and absolves the seller of this responsibility but I'm no expert on this subject that's for sure.

I can certainly appreciate taking responsibility for the car if it was bought as is where is. Up to you then how you handle this.

Be sure the intake from the air box to the throttle body is free of any trash, leaves and such.

Tamaren

Update: Passed emissions with flying colors, seems to be remedied. Drive cycles fixed the problem.

Schnell Gelb

Care to speculate exactly what "Drive Cycle" did the trick ?
Otherwise in the immortal words of a well known M96 mechanic : " I'll be back!" The CEL that is.