The Pro Series EFIE/MAF Tuner for HHO kits

One of our readers, John, suggested I write more on the Pro Series tuners and where to start when using them. That was the plan already- thanks John! In fact, we will be putting new series of videos together covering the installation of our hho kits, the setup, tweaking, and troubleshooting as well as installation of the efies! I will send out emails to our private list and subscribers as those are uploaded- so make sure and subscribe!

The Pro Series Tuners

Along with our advanced EFIE/MAF tuners which essentially cover the MAF or MAP sensors and anywhere from 1-4 O2 sensors (see more about those on previous articles linked below), we also offer a more advanced tuner called the Pro Series (gasoline only). If you havent read the previous articles- please catch up with part 1 and 2 on links below:


The Pro Series is more advanced and is designed for the newer vehicles with more sensors and more computer controls. The old OBD1 systems (pre-1996 cars) was very simple and had 1 maybe 2, O2 sensors, and/ or a MAF. As cars progressed, the fuel maps and computer controls did too. By 2005-2006, mfgs started using additional sensors, and by 2010 -2012, it seems most started using the additional sensors. 

I am referring to the addition of both the IAT (Intake Air Temp) and the CTS (Coolant Temp Sensor). The first one is usually tied in in the same wiring harness as the MAF and measures the air temp coming into engine.The second one measures the temperature of the coolant. Both in more modern engines are used to determine fuel maps, and ultimately how much fuel to deliver to the engine.


If the engine computer determines the air (using the IAT) is say 120 degrees F, it is programmed to LEAN out the fuel. If it is 35 degrees F, it is going to richen up, or add more fuel. When we adjust the pot on the Pro Series, we are telling the ECM that the outside air is Hotter than it actually is- so the ecm chooses the leaner fuel map. Now, mind you, the engine is not harmed in anyway. The computer just thinks it is hotter outside, then it really it is, so its time to cut back the fuel. We NEVER do this without adding in an alternative fuel, such as our HHO kit, or you run the risk of burning valves, but WITH the addition of HHO gas, the engine cuts back fuel, you add it back in with HHO, and the result is less gasoline burned, while maintaining power and gaining mileage (since you are extracting the fuel from water to compensate).

Same goes with the CTS. If the ECM thinks the engine coolant is say, 5-7 degrees hotter than it should be, it signals a leaner fuel map to lean out the gas and cool the engine back down. Remember, we are NOT actually making the engine hotter, we are making the computer "think" the engine is hotter to lean out fuel.

It really is the same thing with the O2 sensors and MAF. We lower the millivot signal of the O2 sensor so the engine thinks it is running too rich, and the computer chooses a leaner map.

Remember, never use these type of product without injecting hho or you could damage your engine. But when used with a quality HHO kit like we manufacture (shameless plug), they can give you more power, more mileage and lower your emissions for a long time. 




Robert Volk
Robert Volk


5 Responses


October 22, 2015

I am buying a camper (rv) f-550 diesel engine will your product work on it?


September 18, 2015

Richard – all wideband vehicles use wideband in front sensor(s) only, and always narrowband in back (downstream).
Thats why our wideband efies have the front two designed for wideband, and rear 2 for narrowband. But you dont need to use all 4 – use 1, 2 or all 4. Works the same no matter what.


September 02, 2015

2011 Toyota Tundra 5.7L 8cyl has two oxygen sensors one upstream one downstream so which tuner wide or narrow band?


August 24, 2015

Kevin – yes. We recommend you either connect the power lead of the pro series tuner to the HHO generator relay or install a separate on/off switch to turn it off in the event you need to disable for any reason. That will automatically restore all settings to factory OEM. We have ours installed with a switch to turn on/off separately.

Kevin Gregg
Kevin Gregg

August 22, 2015

Question: If you have a problem with the unit at some time, can you disable the pro series to not do damage? Say your on a trip and it has a non repairable problem at the time, can it be disabled and how?

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