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Miller MAF Systems

- S38 Software update

Miller Performance is aware of some group buy members having had a rich running conditions. Miller Performance has been working with a few helpful customers to identify and solve the problem. However, it took more time than we had liked only because we couldn't find a local car to try the software with our dyno. Well, we found a local customer who wanted a MAF for his S38 so we could be sure that we figured out the problem areas.

We tried the software that many were having problems with and we did see some issues. We have made the needed changes to the maps so that the overly rich condition is gone and the O2 sensors can do their job.

The S38 has cold start maps. These maps are used on start up when the engine is not already at normal operating temperature. From the factory, these maps are rich, so if you still are getting rich startups don’t panic; this is normal and goes away once the ECU sees the required temperature to move out of the cold start map.

Secondly, everyone needs to make sure, 100% that their O2 sensors are working as they are supposed to. The O2 sensor will compensate for rich/lean conditions always helping to keep the Air Fuel Ratio in check. If your O2 sensor is working intermittently or not at all, your car will always be running rich. We have the maps on all our O2 controlled cars to be a little rich to prevent harmful detonation if the O2 sensor fails. So again, make 100% sure that your oxygen sensor is working properly ALL THE TIME.

Finally, we have guaranteed our selves that the Air Fuel Ratio is in spec on wide open throttle and part throttle, with an average AFR of 12.9 to 1. With part throttle cruising staying around 13.5 : 1 to 14.5 : 1 we have eliminated the rich conditions that many were having. Again, your O2 Sensors will keep this in check if they are working properly.

Getting the new software

If you are in need of the software update for the S38, all we ask is that you cover $5.00 for shipping. Please send us an email with your address. Mark in the subject line, your name and "software update request" to This e-mail address is being protected from spambots. You need JavaScript enabled to view it We will double check with our records to make sure the original purchaser is receiving the update free of charge other than the cost of shipping. As stated, we offer a lifetime warranty to the original purchaser as long as they own the car and or product. Those who have purchased the MAF system second hand are not eligible for the free update.

You may send payment via PayPal to This e-mail address is being protected from spambots. You need JavaScript enabled to view it , or, phone in with Visa or MasterCard.