connorville

Any chance anyone can help me with a few fault codes?

I have changed the distributor cap as it had a ton of carbon on it. All spark plugs have been replaced. Car currently has 80k miles. The spark plug leads were replaced within 4 years. SAI valve was just replaced. When the valve was out, compressed air was blown into the orifice and air could be felt on both sides of the exhaust. The right bank had less air it seemed than the left bank. The car has a TPC supercharger. I have read a few times that not having the OEM belts will cause all sorts of issues. Just seeing if perhaps I can learn a few things from some members way more knowledgable than myself. Engine idle is not that rough. Do have slight puff puff nose on right side though at idle.


Appreciate the help!

-Connor

pp000830

Here are the two mystery codes:
175 Intake Manifold Resonance Flap P1516 P1515 P1512
209 intake Manifold Length Tuning P1593 P1594 P1595

You have multiple codes probably all related to a misfire in cylinder six. Look at distributor belt, Rotor, cap, plug wire, injector?
Other codes seem to be caused by having the normal intake removed or the air injector system.

connorville

Appreciate it. I will try and pull the injector and plug wire to take a look. The rotor and cap were just replaced as of this week. I did not check the distributor belt but probably need to. Is there something I should look for to test on the plug wire other than continuity/dirtiness? I also am not sure what else to do for the air injector system other than dismantle the exhaust and try to hone out the little ports near the exhaust valves.

pp000830

You can inspect the ends of the wire and probably do a continuity test to make sure the conductor isn't broken however it may be better to replace that one wire. Someone on Renlist probably has a used but serviceable wire set they can send you or if you go to a Europen car auto parts supplier they can probably help you. I even think you may be able to disassemble the existing wire and reuse the ends on a new conductor purchased online. Also, a racing parts supply house such as Summit Racing may be able to help you.

As you probably know the air injector system has no impact on performance, it is just annoying because the fault code illuminates the check engine light. Also, a bad air check valve, leaking air hose, faulty air pump, or deteriorated wires (known issue) on the back side of the engine leading to and clamped above the air pump can also cause the same light to come on. In the case of the wire deterioration, I would check this any time you have access to the back of the engine for example during a clutch replacement.

If the secondary air injector ports are reported as by OBCD as clogged. I have no experience with this, however, the previous owner of my car did. I have read antidotal notes such as it shows up more in cars that have spent most of their life in hot climates and that it is related to valve guide wear as some have asserted that the original guides are made of a slightly too soft metal. I have also read that once the valve guides are replaced the problem seems to not return. There is more than one approach to fix this issue or simply getting the light to stay off for inspections:
 Remove the exhaust manifold & air supply and clean the passages/ports with a wire snake made from a bicycle brake cable attached to a hand drill & flushing with cleaning solvent. With this process you will replace the check valve, some do this as a DIY project;
 Add electronics so engine management thinks the clog does not exist, something that may not be legal as well as a disclosure issue when you sell your car, also a DIY item or;
 Disassemble the engine to clean the ports/passages and replace the valve guides, sometimes part of what is called a top-end rebuild. The official Porsche solution, the one your friendly neighborhood automotive shop will $love$ to recommend.
 Clear the OBD injector code and run through a prescribed driving procedure that triggers three of the five emissions related READY codes needed to make the car pass emission inspection in most states. The will enable your car to pass inspection, however, the light will return.

Jay777

This is correct. Your car won't throw any SAI codes unless the AIR monitor is READY so if you try this, make sure the 3 monitors you set READY don't include AIR. A couple drive cycles to do this are described Here . Post 98 speculates that the "SAI Drive Cycle" may end up being a BMW (or other) drive cycle with no cooldown - something I will experiment with more this spring and report on. It does work and is free and legal.