On the next weekend I prepared the car for a smog retest. I topped off the coolant, which took a full gallon with properly venting the system at the engine block outlet. The car drove well although the fan kept cycling. The coolant temperature was not able to move above the first dash on the gage. Even if I drove harder, the needle did  not budge. At this point I think I will add a complete cooling system rebuild to my “to do” list. I make it to the smog shop and they gladly retest without cost. They run the car for an oddly long time. It fails NOx at the 25 mph. What!?!? Turns out that the car was previously entered in as an 84, not 94, which means it was previously run under a different dyno load and higher limit. The year was entered in by hand and was not off the VIN. They go ahead and retest again after trying to warm the car up. Failed again, better, but still a fail. It’s off by about 50ppm. So close. Poway Smog Station let me know that they will retest until I get it to pass.

My first plan of attack was to change the O2 sensor, spark plugs, and filthy K&N air filter. I don’t understand the previous owner. He installed a K&N filter but clearly never cleaned it for the 10 years he owned the vehicle. I was already going to change all these parts but figured I try that now before I go for a new cat. Just in case, I contacted a great parts shop, Autobahn Dismantlers in El Cajon, to see if they might have an OEM 968 cat lying around. These guys are usually fair and easy to work with. Sean let me know he will look around as he believed he might have one. That will be plan B. Maybe I’ll get lucky and he will have a new one which I would be inclined to purchase whether it passes smog or not. The current one is fairly rusty and shows signs of weld repairs. Meanwhile I order all my other parts. I got a great deal on a Bosch O2 sensor direct fit from Rock Auto. Rock Auto is a great cheap place for parts but I would not buy plastic or rubber parts from them for a performance or classic car. Although I have never had a bad experience with any parts for my daily driver vehicles, the part age and storage may vary. The rest of the parts along with all the parts I need for a cam chain, timing belt, pulleys, and water pump I purchased from a new site, Vertex Auto. A friend of mine sent me a10% off code when using Vertex Autos new website they are testing out. The prices even without the discount beat my choice supplier Pelican Parts. The Laso water pump was $100 cheaper. The website does lack some key details such as images, diagrams and descriptions. At times it was difficult to differentiate between Porsche genuine parts and OEM . I decided to verify part numbers with Pelican Parts.  The site claimed free shipping that for some reason did not apply to my order. After speaking with Vertex Auto, they cleared it up. Turns out it’s either the 10% off or free shipping. They still gave me free shipping though, so that was nice. They are really easy to work with and will probably purchase parts from them again, if the parts arrive as described.