DBJoe996

The original Porsche MAF sensor is 996-606-123-00-OEM

The Bosch OEM MAF sensor is 996-606-123-00-M14.  I don't know the difference between the M14 and MS19 and I don't think they are revisions.

These are for cars without E-Gas.

Your DME should be at ME5.2.2 and you can check it out at the time you hook up the Durametric.

Looks like the correct MAF part number for a 99 C2.  Is it OE Porsche or Bosch OEM or aftermarket?  Our cars are really picky about the correct MAF sensor.

The P1123/P1125 seem to always point to the MAF sensor.  See here

Start with the fuses in the fuse panel.  Why did you have to jump start the car?  Bad battery, low battery will cause all sorts of electrical problems.

Yes.  Pull the pins down and the clips will open.  Move them slightly out of the way and you can lift the seat bottom up.  Careful, there are some wires attached to the seat bottom that need to be detached before lifting and moving the seat bottom forward and out.  Best to get the seat in a position to do this,  and move the steering wheel all the way in to make more room.  It is also a good idea to disconnect the battery before doing this since the seat pad affects the airbag system and seat belt system.  Take a picture of the wiring harness and connectors before disconnecting them.

This certainly is going down hill  fast.  I would stop locking the car because it may get to the point where it does not unlock.  It does appear more and more to be a problem with the immobilizer.  When you insert the key in the ignition, the passive RFID pill in the key is read by the immobilizer and a two way communication occurs between the immobilizer and  DME.  This two way communication says...yes this is the right key so go ahead and power up the systems, fuel pump, ignition circuits and so on.  So you are getting part of the two way communications between the immobilizer and DME, but not all of it.  And the recent episode of the fuel pump running without the key in the car says to me something is shorted.  I also would start removing as much of the wet carpet as you can under the drivers seat.

One question - when you put the new battery in, did you connect the + cable first and then the - cable?  How did the cables and connectors look?

Maybe this will help 

Weird gremlins.  Usually a result of a bad ignition switch, but all you did was replace the battery.  Wondering if the immobilizer is keeping the car locked down.  Maybe try the fuse panel jumper again with the key in the ignition and turned to ON (not start).  Good luck on fishing out the emergency release cable.  And after you figure all this out, it is a 15 minute job to relocate the front trunk lid emergency release cable down to just behind the bumper tow hook plug.  Saves hours of frustration.  Pop the bumper plug and there is the emergency release cable.  One tug and you are in.

What does the voltmeter gauge in the instrument cluster read when you turn the ignition to on?  Should show almost 14V.  You cannot use the fuse panel pop out with a battery charger.  It does not provide the amps needed.  Hook a strong 12V battery to the fuse panel pop out and grounding point.  There is another emergency release cable for the engine lid under the left rear tail light.  Take a soft smooth wedge and make some space between the bottom of the light and the bumper.  You probably can fish it out with a self made hook.  That will gain you access to the jumper points in the engine bay where again you can hook up a good 12V battery (or jump from another vehicle) to see what you can get working.

Might be a good idea to check all of your fuses.  I recently bought a box of blade fuses and it came with a little tester that you just touch to each fuse to check it.  Took about 2 minutes to run through the whole fuse panel.

A hair dryer set on low would help dry up the carpet.

MAF sensor wiring has nothing to do with the AC.  You should be able to remove the air filter box and still cycle the AC compressor on/off with the engine running.

Worth a try - disconnect the negative battery lead and let the car sit for 30 minutes.  That should reset the DME to base values and programming.  Other than that www.ecudoctors.com

A mechanics stethoscope comes in handy when checking for noises that only occur while the engine is running.  The AC compressor could very well be the source of ticking.  When you turn on the AC, the compressor electromagnetic clutch engages and stops free wheeling.  So the tick could be from the clutch when it is not engaged.  You can also check the other pulleys, power steering pump and alternator for noises as well.  You want it to be something like this and not something internal to the engine.

Low mileage is really not good with these cars.  The more they are driven the better off they are.  Garage queens develop all kinds of mechanical issues, just from sitting and not running.  99 C2 with 143K miles.  Get out and drive!

Not seeing much out of the ordinary here.  AOS breather hose goes to Bank 2.  That black and white thing is a vacuum check valve.  Check the plenum clamps and make sure they are squared up and tight.  Clean everything up and monitor.  The inside of the plenum looks good.  I always replace the TB O-ring when pulling the TB for cleaning.

The horn beeps and lights flashing is the alarm system telling you there is a alarm system zone fault somewhere.  Could be an open (or maybe in this case closed/locked when it should be open) zone.  Zones are: drivers/passenger doors, trunk lid, engine lid, glass (targa) top, gas cap lid, center console lid, and if you have it the glove box door. There are also two interior sensors in the overhead that detect motion when the car is locked.  I think getting to the battery and disconnecting is a good idea.  However, you have a problem since the trunk is not opening.  First thing to try is actually seeing if the trunk is already open.  Put your fingers under the trunk lid and try pulling up.  Second is to locate the emergency release cable under the passenger side headlight.  Unfortunately you need to pop the headlight out to make this a simple exercise, and  you can't do that without opening the trunk.  So you have to pull the  passenger wheel well liner and fish out the cable from behind.  Hopefully your wheel lock socket is not in your trunk!

I agree.  It seems like an alarm system fault....key fob not working to unlock the car, engine lid and trunk lid releases locked down,  car not starting.  I know it might be a real pain in the neck, but you might consider putting the old door latch back on to see what happens.  Are you sure you got everything hooked back up right on the door latch?  BTW, did you disconnect the battery to remove the door panel?

Have your DME flashed to a ROW (rest of the world) program and all your SAI errors go away and stay away.  Check out ECU Doctors for that.  All the SAI system does is pump air into the exhaust system while the cats are warming up.  On a 20 year old car, frankly, in my opinion, it is a waste of time.

I find I have to push and  hold before it zeros.  Takes 2-3 seconds.  Try that.

The mirror positions are stored in the seat memory module under the drivers side seat.  In other words, the mirror positions are programmed along with the memory seat positions.  When you unlock the vehicle with a key fob that is programmed to the car, the seat and mirrors return to a preset programmed position for that key fob.  Follow the steps in your owners manual for resetting your memory seat and mirror positions. 

Not quite sure...but I think that is just a plug (called a lid) on the cylinder head.  Could be #48 here or #41

I would clean that up real well and see if it is weeping around the edge.  I would also measure it because what I provided in the link says it is 18mm or it could be the 10mm.  Then you have two choices, pop it out and replace, or pack that whole thing full of heat/oil resistant RTV gasket sealer.

Here is my engine number for a 99 C2 with a manufactured date of 7/98 (thus my car has an engine made in 98).  So from your description M96/04, from Model Year 2001, 661 should be the next sequence, and the last five digits are the engine serial numbers, ranging from 00501 to 60000.  Yours is 14453.

Usually if it is a factory replacement engine it will have an AT in the engine number such as M96/04ATXXXXXXX.

It could be an engine from a donor vehicle.  See chart:

In no way do  the VIN numbers and engine numbers match on a Porsche.  About the only way to find out if the engine is original to the car is to order a Certificate of Authenticity from Porsche with the VIN.  That should list the original engine number.