First, some history with my efforts ......
The van has 156,187 kms or nearly 97,000 miles on it, runs well getting from 29 to 31 mpg (Imperial gallons) on longer Highway trips of 200 to 300 miles. Shorter trips, under 75 miles, the highway mileage is between 22 to 26 MPG... suspect it is due to the weight of the fuel, I keep my tank topped off all the time, mostly due to doing test runs. City driving gets me 17 to 19 MPG. All the above without HOD or any other enhancers operating... .
I have run savefuel.ca, Water4Gas single cell plus multiple cell and a smack booster without any significant increases in MPG, sometimes a decrease. All of the above has been without any other enhancements added. The reason they were not added because I did not see any initial increases in MPG, (and then the drop to less mileage than they were getting originally) that many report with their various boosters.... .
I ran across "Tuning for Mileage" by mpgmike and read it, studied it over and over again. Ordered the EFIE from Eagle Research, built the Map Voltage Regulator, located all the various sensors, etc. After receiving the EFIE and having built the Voltage Regulator I had problems trying to find the wiring for the O2 sensor and the MAP sensor, so decided to get a local garage to hook them up for me.... well, due to the way things were crammed in and inaccessible without removing different items it took 2 1/2 hours to complete that job..... and you can imagine what the cost was.
I built a HOD booster using 2 inch by 7 inch PVC pipe, with 5 SS threaded rod electrodes approximately 6 1/2 inches long, the booster is connected to a Reservoir/Bubbler by two clear plastic tubes, one being the output for gas and electrolyte to the bottom of the reservoir, and the other a return working by thermal syphoning action. Another bubbler is just before the air intake. This generates about .75 LPM at the moment. The booster is located in front of the rad,low down and the reservoir is as high as I can get it at the back of the engine compartment, for the thermo syphoning to work properly.
I did the whole tuning process, but ran into so many trouble codes that I re-did things one at a time. Got the EFIE set at 365 millivolts without tripping the closed loop to "Open". Anything higher would go to open loop. Tried a short test run with only the EFIE on. Got 34.45 MPG... encouraging!
Did the CTS: using 3.9 k ohms. Temp at 206 F . No codes
Did IAT: using 3.9 k ohms. Went to Open Loop... could not set EFIE to go to closed loop, removed resistor. Got closed loop again. left resistor out for time being.
Did the MAP: Set it to 3.50 volts. Anything less would trip a MAP code
Did MAF: using 22 ohms, no good.. MAF codes. Same with 10 and 15 ohm, codes come up intermittently. Finally tried the 10 and 15 ohm resistors in parallel, no more codes.
O2 Sensor, AFR adjustments etc: Over a period of 3 days I have manage to increase the EFIE voltage to its present setting of 375 millivolts by small increments, otherwise I would get Open Loop. Seems after several hours the setting will not trip to Open Loop, when done this way.
Last night with everthing connected (including the resistor for the IAT) and the hydrogen running I got 34.21 MPG on a 39 mile run without tripping any codes.
All my MPG checks were done by filling the tank to overflowing and doing the calculations from there. The ScanGaugeII is not at all reliable for checking MPG once you have made changes to your sensors etc. Most of the readings are all over the place after such changes.
I thought I was getting close to seeing something worth while, however, after doing 9 test runs in the last 5 days using different settings, I am beginning to think that my earlier observations regarding HHO were correct.... that all the gains most people are getting is from the fuel heaters, PCV enhancer, EFIE, Map and Maf enhancers plus the Acetone, Xylene etc that is being added, and not from the hydrogen!
My best mileage gain was by running the EFIE only.
Time for a reality check....... .