Wow wow wow. I couldn't believe my eyes. 49.6mpg to church and back. Friday evening I tested the resistors again just playing around. I used 110 ohm, 4.7k ohm and stock IAT on a ten mile stretch of highway. TPS is much higher with the resistor 3-10 points higher average between 55-60mph.
So today before church I popped in the 110 ohm and headed out. Conditions were
sunny and dry
Load was 3 adults, 1 child, baby junk, and my welder (100lbs) and jack/spare.
Trip there was 47.5mpg. Using beltway, speeds 60-70mph. No codfishing for first 15minutes(20 minute trip)
Trip back mileage improved to 49.6mpg. Driving through city. Lots of lights. Temp improved to the 50s.
02 Saturn SL
for pics click the link below
What is more representative of the engine block temperature? The engine coolant temperature or the exhaust temperature?
... blah blah blah ...
To make a short story long, the thread segwayed to the reason I wanted to know the engine temp, IAT resistors and A/F ratios. Soooo, I did a test. It is *far* from perfect, but here is a picture of the data :
1 - I should have disabled the HAI (Hot Air Intake) in order to create a "stock" Saturn baseline configuration. Still, the HAI is "real" hot air, as opposed to the resistor, which *should* be in conflict with the 02 sensor.
2 - I should have a better and longer road to use for ABAB tests. A longer road might show the MPG go down over time as the ECU/PCM adjusts to the 02 sensor.
3 - I should do many more MPG tests, maybe 5 in each direction.
4 - I should have more fake IAT resistor settings for different temperatures.
5 - These are scangauge-based MPG figures. I can't explain it correctly, but the scangauge uses the "injector pulse width" to calculate MPG :
I thought it read the injector pulse width from the ECU and calculated fuel usage from that.
A shorter pulse width with each IAT resistor mod would imply lean-burn because the composition of the air coming into the car is the same for each test. Could the car be maintaining speed with less fuel and less air? The scangauge can't show me this for the purpose of this kind of test because it doesn't average MAP and TPS over time. I would need something like the CarChip for that .
However, I still feel good about the test because I think a clear trend is present.