Secondary air readiness STILL not ready for CA smog after over 500 miles

[geoff]

There were several posts on the topic, but after reading through all of them, I don't think I ever found a definitive solution as to fixing the secondary air readiness. About a month ago, I started driving to get my '01 986 smogged and got a CEL. Code reader showed it as a vario cam bank 1 problem, and after some diagnostics, it ended up being the actuator (which also includes a new solenoid), which my mechanic at the dealer replaced. My car drove better than ever, but after driving around for several days, when I went to get it smogged two readiness indicators weren't set. I tracked down the drive cycle description, followed that many times, and every time I checked the secondary air readiness still wasn't set.

 

I made a trip back to the dealer today, head mechanic confirmed the secondary air system is functional by turning it on with Porsche tester, no fault codes showing, but still couldn't get secondary air readiness to set. He disconnected the battery, hoping clearing everything would solve the problem, so I drove around doing some errands, and by the time I got home everything was good to go except secondary air readiness. So I still can't take it in to get smogged.

 

I'm going to drop it back off at the dealer later in the week so they can do a cold start in the morning. Any suggestions as to what is known to solve the problem since all the prior posts on this subject?

[JFP in PA]

Some of the 986 models were plagued by incredibly long runs to rest the I/M Readiness triggers in the DME; hundreds of miles after all faults were correctly repaired were not uncommon.

[geoff]

On 3/14/2023 at 9:46 AM, JFP in PA said:

Some of the 986 models were plagued by incredibly long runs to rest the I/M Readiness triggers in the DME; hundreds of miles after all faults were correctly repaired were not uncommon.

No kidding! But over 750 miles seems a bit excessive.

 

I was going to take my car back to the dealer and leave it so the head tech could do a cold start in the morning and see what's going on. When I started to go out there this afternoon, I tried revving the engine to 2800 RPM for 2 1/2 minutes with the defroster on, instead of letting it idle to start the drive cycle. Then plugged in my cheapie OBD tester, and lo and behold, all readiness indicators were set, including the secondary air injection. I didn't go out and buy a lottery ticket, but I stopped by my usual smog check place, and all readiness indicators were still set, no CEL showing, and my car passed the smog test, so I'm good for 2 more years.

 

I went by the dealer afterwards, my service writer said there's nothing for them to do, then I chatted with my mechanic for a while. He hadn't heard about this, but figured at 2800 RPM there's a lot more air flowing through the system, which gets the onboard computers to recognize readiness.

[Schnell Gelb]

This 'fix' has been discussed here on Renntech previously by several others. Do not exceed 3000 rpm until the SAI pump completes after a cold start- or it will fail to work.

In my experience it is a very useful band aid for getting through the Smog Test if you have undetectable SAI issues.

I'd expect that eventually you'll get a MIL and "not ready' issues in future.

I just disregard these and do the drive cycle just before going to the Smog test.I'm fortunate that I now live in an area where the impractical official Drive Cycle can be done safely and without interruption.

It seems to trigger the MIL after 3 more cold starts ,so go straight to the Smog Test !

Clearly there is some component or design feature that is marginal. I don't know why the just under 3000 rpm while stationary at a cold start fix works.

I am suspicious of the small diameter holes that channel the SAI air into the exhaust ports.If they get partially plugged with carbon this problem may be created.

There are other threads on cleaning  these lpesky ittle ports.

If you decide to r&r the exhaust manifolds to do this cleaning ,be sure to read about problems with rusty,snapping bolts and upgrades to stainless studs.

The SAI/Smog issue is such a nuisance that I also replaced/upgraded almost every component in the SAI system. You only want to do it once !

 

[geoff]

2 hours ago, Schnell Gelb said:

This 'fix' has been discussed here on Renntech previously by several others. Do not exceed 3000 rpm until the SAI pump completes after a cold start- or it will fail to work.

In my experience it is a very useful band aid for getting through the Smog Test if you have undetectable SAI issues.

I'd expect that eventually you'll get a MIL and "not ready' issues in future.

I just disregard these and do the drive cycle just before going to the Smog test.I'm fortunate that I now live in an area where the impractical official Drive Cycle can be done safely and without interruption.

It seems to trigger the MIL after 3 more cold starts ,so go straight to the Smog Test !

Clearly there is some component or design feature that is marginal. I don't know why the just under 3000 rpm while stationary at a cold start fix works.

I am suspicious of the small diameter holes that channel the SAI air into the exhaust ports.If they get partially plugged with carbon this problem may be created.

There are other threads on cleaning  these lpesky ittle ports.

If you decide to r&r the exhaust manifolds to do this cleaning ,be sure to read about problems with rusty,snapping bolts and upgrades to stainless studs.

The SAI/Smog issue is such a nuisance that I also replaced/upgraded almost every component in the SAI system. You only want to do it once !

 

 

Unfortunately, I live in CA, so readiness not being set means the smog test can't be run. After around 2K miles over the past almost half a year since getting smogged, no check engine light. I'm going to hold tight and see what codes look like in about a year and a half the next time I have to go through the whole smog check experience again

[lukechang]

I ran into secondary air system monitor incomplete issue past few weeks with my ‘01 996. I made many cold starts but failed to get it ready for smog check. I use a WiFi ODB reader with ODB Fusion app. It showed no fault code and no pending code every time I completed a drive cycle. At the end I decided to use my Foxwell N809 to check. It showed P1130 code. I cleared it and did a drive cycle (cold start idle 3 minutes, 20-30 mph 4 minutes, 40-60 mph 15 minutes). Everything cleared and ready except secondary air.  I waited for engine cooled down and drove a around block neighbor immediately without cold start idle. The secondary air was then ready.

The issue I noticed during this exercise is that ECM has a third place storing fault code for history in addition to the recorded code and pending code. Maybe it is a version before permanent code became official in recent years.  Not all the scanners on the market are able to read it. I did a side by side comparison between WiFi ODB and Foxwell at the same time, only Foxwell showed code. With any hidden code in ECM, the secondary air would not complete.

[JFP in PA]

Welcome to RennTech 

 

You are witnessing the limitations of using a global OBD II tool instead of a Porsche specific tool. I suspect that there are either pending or active codes you are not seeing.  The P1130 code is good example; that is the code for an overly lean condition on bank two, possible due to an air leak in the intake system, low fuel pressure or delivery rates, or a fouled injector; any of which would prevent the car from reaching IM Readiness. 

[geoff]

My problem as originally posted did not show anything pending or actual as far as fault codes on the Porsche dealer's Porsche diagnostic computer tool. They told me to drive it a bunch and the readiness would set itself after a few hundred miles or less. Many, many hundreds of miles later, I resorted to the half throttle immediately after starting and that set the secondary air readiness finally. It's likely some sensor component that still works on these 20+ year old 986s enough to drive around without throwing an error, but is still out of spec

[Schnell Gelb]

Speculating - the P1130 (lean on Bank 2 ) may be caused by a detached/deteriorated  vacuum line . Sometimes diagnosing this SAI issue requires physically digging into the components . None of the parts are very expensive or complicated and the system itself is covered in many posts. The problem is awkward access. Probably due to replace all the rubber and plastic parts anyway ?

[Schnell Gelb]

6 minutes ago, geoff said:

My problem as originally posted did not show anything pending or actual as far as fault codes on the Porsche dealer's Porsche diagnostic computer tool. They told me to drive it a bunch and the readiness would set itself after a few hundred miles or less. Many, many hundreds of miles later, I resorted to the half throttle immediately after starting and that set the secondary air readiness finally. It's likely some sensor component that still works on these 20+ year old 986s enough to drive around without throwing an error, but is still out of spec

Glad it worked for yo and thanks for posting the details. Wish I knew exactly which component is marginal and how to resolve it. My guess is that regardless of your fault code, your car performed the same .That's my situation too.

[Schnell Gelb]

Mine is a 2002 Boxster S. The codes are P0410 and P0411.

The short version : the vacuum hoses were collapsing at low speed idle and/or gasket blocking port - see far below for details.

Here's some info. and ideas to help those forgotten souls who battle with their S.A.I. system every 2 years to pass Smog.

I've upgraded &/or replaced every single part of the S.A.I. system. Specifically I replaced all the vacuum lines and silly elbows with high quality silicone hose and brass, barbed fittings.Beware ,silicone hose is not very ridgid so it's walls are prone to collapsing under high vacuum and you would never see/diagnose that ! Suggest you use very thick wall hose. I replaced my regular dimension silicone hose with 3.5mm i.d. with 9.5mm  o.d. by HTS.If you select the blue or yellow color it is easier to trace in the dark area under the inlet manifold. I posted this suggestion many years ago and on my car it is still working well.

 What I didn't explain was that I deliberately re-routed and extended the vacuum lines so they are draped on TOP of the passenger side inlet manifold, not buried underneath it. I also inserted 'test tees' on top.

The photo below shows how easy it is to do vacuum tests on different sections of the system.You can connect a smoke machine($80) to indicate large vacuum leaks. It is enormously beneficial to be able to test the vacuum system BEFORE you start removing the inlet manifold to chase suspected leaks. By pinching off sections you can test individual components to see if the system holds or passes a vacuum applied with a simple vac pump (cost less than $50).

I also replaced all the suspect components. Before you order components or even look at a  parts diagram, be aware the components changed after 1999 MY and again in 2005. In my case I have the newer shut-off valve a.k.a. Kombi valve.The best parts diagram I found is on Auto Atlanta but be very careful to find the correct year parts diagram :"Porsche Boxster 986 M96.21/22 air injection 00-02 M96.23/24 03-"

You may have found other parts diagrams but without model years, part names or part numbers. Confusing. So below is my list of suspect components with full info. to help you . Please correct them in this Thread if you find an error. Diagram annotated by another SAI warrior is in next Post below.

Test all new and old components before you fit them because once you do all the work of reinstalling the intake and maybe the alternator ......

The prices are from Auto Atlanta .You may find cheaper generics elsewhere.

 

.#1 "Air Injection Pump" . This seldom fails and is easy to test.The air flow should be like a hairdryer on the high setting. 99660510401 .The Porsche replacement is $2500 ! A good, used one is $25(Specialized German on flebay) , a generic, new one is $70.

 

.#22  the black and white drum shaped "Check Valve" that connects close to the engine air intake.Make sure you don't install it backwards !

96411095002    $23

 

.#16 "Vacuum Tank" with the oval or dome shaped top. Infamous for hairline cracks at the base which are invisible and require testing with pressure under water.Be sure to test the new one before you fit it !  99311014003   $23

 

.#18 "Change over Valve" . This has 2 vac ports(in+out) and an a polarized 12v connection. 99660512301. $34. If you test a new valve with a vacuum pump+gauge, you may see it hold high vacuum for a few moments then very slowly bleeds away. Strange.Significant when trying to locate leaks in the entire system !

 

.#15 "Shut Off Valve" aka Kombi valve . 99711324990, $115.

 

Once you've replaced the suspect components and connected all the new vac lines and new fittings , suggest you do a complete vacuum/power test 

Here's a controversial test once the Intake manifold is refitted and you are ready to start for the first time. The idea is to get instant physical evidence (from a cold start ) that SAI pump air is passing through the entire exhaust system. Pour one dose of Seafoam down the SAI Pump hose and reattach it. Start the cold engine. If the system is flowing correctly , you should get an unusually dense but brief cloud of white smoke from the exhaust.Most of the Seafoam will drain vertically into Bank 1 so this is not confirmation that the system to Bank 2 is perfect.

Durametric on the  forward O2 sensor for Bank 1 &2 is a more reliable test.

 

Edited March 26 by Schnell Gelb

[Schnell Gelb]

Here is parts diagram of the SAI components with the old Change-over Valve and separate :Check valve.The so called Kombi valve combines both functions in a single part # 99711324990 $115. Suggest eliminate as many elbows and hard plastic lines as possible by using very thick wall silicone hose. Use barbed brass fittings instead of plastcicthat may become brittle.

Edited March 13 by Schnell Gelb

[Schnell Gelb]

Note #15 the Kombi valve is different in the parts diagram below to the one above.

Beware of part # 99611323350 "Gasket Hexagon" !

It is actually a triangular shape not hexagonal. If you fit it upside down(see photo below) or allow it to move when fitting ,it will partially cover the passenger side SAI port causing code P0410. The Drivers side would not be affected  so not related to P0411. To check this I marked the edges of the gasket with red marker and used a pencil beam inspection light to check the gasket hadn't been dislodged.  A thin smear of high-tack gasket sealant like Loctite 1525607 may help ?

But before you do any of this, use compressed air to confirm the port for Bank 1 and the tube for Bank 2 are flowing out of the exhaust tips. You'll need an assistant for this and a high flow ,low pressure air source. Maybe a Shopvac outlet as an alternative source? Use the same rig to check after you've refitted the Kombi valve and gasket by using a vacuum pump to open the valve.

Then attach the electric change over valve. I rerouted mine so the hose is long enough to sit on top of the intake manifold after I refit it. It is easy to unclip from the bracket that holds it close to the Vacuum Accumulator.Activate the valve with a 9v battery(smoke alarm size) and check you still get air flow out of the exhaust.

I suspected the problem on my SAI system may be the ECU is not supplying power to the Electric Change-Over valve during a cold start. Yes, Durametric will make the relay audibly click and illunimate a Bosch EV! Noid light but is the ECU doing it in a normal cold start ? I needed to rig a test light into it's circuit to make sure the valve is powered for 60+seconds during a cold start, not just when it is 'forced' by Durametric. To manually trigger the valve with a simple switch, use a male EV1 pigtail (Ballenger Motorsports $10).

If this speculation is correct , it will be easy to add a manual switch near the instrument panel in the car  to activate the valve because the valve will be relocated  on top of the Intake manifold, not totally inaccessible beneath it . This wouldn't solve the issue some mention of the SAI needing to run occasionally during some cruise conditions. But at least the cold start problem would be solved in a practical (albeit Rube Goldberg) way ?

Edited March 13 by Schnell Gelb

[Schnell Gelb]

It passes Smog !

All monitors set without a complicated Drive Cycle - just a random 10 mile drive in the country. But why so easy ?

Speculating:

1. it is very easy to not notice that triangle shaped gasket has been displaced and obstructs the valve port. See photo above.

2. regular silicone hose may have been collapsing and preventing vacuum reaching the electric changeover valve. Use 3.5/9.5mm, colored hose.This may explain why the "inc" code appears after letting the engine idle from a cold start. The very high vacuum collapses the hoses so the change-over valve is inoperative. If you do a fast idle -2500-2900 r.p.m. the vacuum is much lower so the changeover valve gets enough vacuum. The new, extra thick wall silicone hose eliminates this and you can verify because the vacuum hose is accessible now..

Whatever the cause:

1. now it is much easier to verify functionality of S.A.I. components because critical parts of the system are on top of the intake manifold, not inaccessible  underneath it.Yes it looks funky but now you can vacuum test it all with the SAI system operating.

2. the Seafoam test was confirmation that at least some secondary air was reaching the exhaust manifolds. How else would you verify that ?

 

btw, suggest you invest in a good 1/4" drive magnetic socket set(or at least a  magnetic 10mm socket and a selection of 1/4"drive extensions.Makes r&r of the Intake manifold easier.No dropped bolts ! If you are dexterous you can even use it for the bolt at the end of the manifold,close to the alternator. That means you don't have to r&r the alternator.If you aren't dexterous and patient, just give this job to someone who is !

Next job a Uaos perhaps?

Edited March 26 by Schnell Gelb