When preparing to tune a Porsche 996 Turbo there will be some inherent mechanical issues to look for as these cars are now ~10 years old. As long as the car is in good working mechanical order the OTS maps and any custom tuning will work great. Mechanical faults may potentially contribute to issues when tuning. We have compiled a list of things to look out for, as well as how to fix them.
The most important thing start with is a boost leak/smoke test. This is the best way to rule out airflow-related mechanical issues on a car before tuning!
We highly recommend you ensure the four items below are in good order before tuning your Porsche 996 Turbo!
- Spark plugs should be changed at 30K miles. The best plug to use is an NGK PFR7B gapped to .027". This will ensure no spark blowout. You will also want to check that the coils are in good shape. The stock coils are pretty strong and have been used in 1400 whp cars. If there is any cracking they will need to be replaced
- We do not recommend the use of Iridium plugs in the 996 Turbo. They can cause break up issues intermittently.
- The F Pipe is a piece of hose that the diverter valves attach to. It has been known to tear and rip, and with increased boost pressure can cause tuning issues. It is smart to replace this pipe with an aftermarket one. Samco makes a good quality F pipe that we recommend be used.
- The stock diverter valves on the 996 Turbo are made of plastic and over time they start to break down and leak. In some cases we have seen them actually explode open from increased boost levels during tuning. This is very common and they need to be upgraded. We recommend the Forge units as they are cost effective and work very well.
- There are 3 check valves on the 996 Turbo that can fail. When this happens it can cause boost control issues and AFR issues. The best way to mitigate these problems is to boost leak test and replace with factory valves so that you are sure there are not going to be issues going forward with tuning.
General maintenance is important as well! Oil changes, coolant level, etc. should be checked to make sure that they are in good shape!