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ddruker · 11-26-2020, 08:27 AM

Unfortunately, it's almost certain that the prior owner knew about the secondary air injection system problems and simply reset the codes before they handed the boxster off to you. I would probably call them and read them the riot act if it were me. They should be paying to fix this not sticking you with it.

After resetting the codes, it can take several starts before the codes come back - so if they cleared the codes just before they handed the car off to you, you are seeing the expected behavior.

The good news is that the most common causes of these codes are very well known. well I concur with the other posters that you should follow the testing procedures that are well documented in this forum so you aren't just replacing parts willy-nilly, the most common things that happen are one or more of the plastic vacuum lines fail, or the plastic vacuum accumulator reservoir fails and leaks.

It is not a big deal to replace the vacuum lines and the accumulator reservoir. Strongly suggest you replace the old plastic vacuum tubing and plastic fittings with silicone vacuum hose with brass fittings and that will permanently solve the problem. The accumulator reservoir is also made of plastic and gets brittle over time and leaks, and it can be very hard to find the leak. I feel like since it's only $20 it's better to just replace it with a new one. A vacuum tester, which costs about $25 on Amazon, is the only unusual tool required for this job. And I would definitely get one so you can make sure that the system is holding vacuum before you put everything back together.

If you remove the air oil separator you will have more room to access the secondary air components without removing the passenger side intake manifold. You may find you also have to remove the alternator, depends how limber you are.

I tested the air pump to make sure it was blowing strongly, and then I chose to replace all of the rest of the components in the system as the total price was less than $200 for everything. About 10 ft of silicone vacuum hose, a few brass fittings, some clamps, a new accumulator, and a few new valves is all that is involved.

So my recommendation would be to first check that your air pump is working, and if it is then remove your air oil separator, then refresh the parts in your secondary air system, at a minimum replacing the vacuum hose and connectors, the vacuum check valve, and the vacuum accumulator, and then testing the rest of the valves to make sure they work properly before you put everything back together and then as a final step install a new air oil separator.

Oh and don't be a dummy like me and put the new vacuum check valve in backwards. That was a real head scratcher since I was testing the vacuum from the output side of the check valve.

11-26-2020, 08:27 AM	#6
ddruker Registered User Join Date: Jul 2018 Location: Palo Alto, California Posts: 59	Unfortunately, it's almost certain that the prior owner knew about the secondary air injection system problems and simply reset the codes before they handed the boxster off to you. I would probably call them and read them the riot act if it were me. They should be paying to fix this not sticking you with it. After resetting the codes, it can take several starts before the codes come back - so if they cleared the codes just before they handed the car off to you, you are seeing the expected behavior. The good news is that the most common causes of these codes are very well known. well I concur with the other posters that you should follow the testing procedures that are well documented in this forum so you aren't just replacing parts willy-nilly, the most common things that happen are one or more of the plastic vacuum lines fail, or the plastic vacuum accumulator reservoir fails and leaks. It is not a big deal to replace the vacuum lines and the accumulator reservoir. Strongly suggest you replace the old plastic vacuum tubing and plastic fittings with silicone vacuum hose with brass fittings and that will permanently solve the problem. The accumulator reservoir is also made of plastic and gets brittle over time and leaks, and it can be very hard to find the leak. I feel like since it's only $20 it's better to just replace it with a new one. A vacuum tester, which costs about $25 on Amazon, is the only unusual tool required for this job. And I would definitely get one so you can make sure that the system is holding vacuum before you put everything back together. If you remove the air oil separator you will have more room to access the secondary air components without removing the passenger side intake manifold. You may find you also have to remove the alternator, depends how limber you are. I tested the air pump to make sure it was blowing strongly, and then I chose to replace all of the rest of the components in the system as the total price was less than $200 for everything. About 10 ft of silicone vacuum hose, a few brass fittings, some clamps, a new accumulator, and a few new valves is all that is involved. So my recommendation would be to first check that your air pump is working, and if it is then remove your air oil separator, then refresh the parts in your secondary air system, at a minimum replacing the vacuum hose and connectors, the vacuum check valve, and the vacuum accumulator, and then testing the rest of the valves to make sure they work properly before you put everything back together and then as a final step install a new air oil separator. Oh and don't be a dummy like me and put the new vacuum check valve in backwards. That was a real head scratcher since I was testing the vacuum from the output side of the check valve.