Hi Greg,
I will reply piece at a time.
It's a good photo -thank you- but I can't zoom in close enough to see what's happening on your TB without going blurry.
Blocked IAC? how did you compensate? by readjusting the throttle idle stop screw? If so, did you also adjust (if possible) your throttle position sensor to reflect that change?
check and see what that's (TPS) telling your computer - that may be the source of overfuelling. a few degrees may make for enough of a voltage change to get the computer thinking it needs to increase injector pulse duration.
Yes I compensated with the idle screw, yes I adjusted the TPS at least the same amount. Now I asked you to only make suggestions based on experience and preferably referencing specific gain that you have seen in MPG. I also did a lot of research on how the TPS functions, I also fitted an air/fuel ratio gauge for probably 2000kms after this modification. The ratio was always in the lean range, the TPS causes the fuel ratio to temporarily flare into a rich status when pedal is depressed for an acceleration phase, the further you press the pedal the richer it will flare to. It then returns to normal airfuel ratio. I discussed this at length with a guy who truly understands computer programs and basically the TPS doesn't do that much to ECU fuel delivery, as I saw by watching the gauge. I don't know what impact there would be turning the TPS the other way but I think I have checked and double checked that it is not causing me any problem.
Another thing I need to have you reconsider is that in your equation, Pressure is NOT irrelevant. (Why bother with converting to Kelvin if you're not going to take all the units involved in the published equation into account? just because you can show a bigger number with your use doesn't mean you're correct; you can't prove what that number MEANS because of the lack of reference to units) Remember, this is chemistry...and there are physics involved before the pistons can move turning a crank and transmission and differential and wheels.
Let's walk through a theoretical calculation using Standard Temperature and Pressure (16 degrees C - 29.92inHg) and one liter (or gallon or Sh!tload...doesn't matter) on one side of that equation :
P1 times V1 over T1 is (29.92 times 1) / 16. that works out to 1.87 ignored Units.
Now, we've got a running engine making 20" of vacuum in the manifold, so P2 is 9.92inHg, and there's still one volume of air, but if it's 70 degrees because you warmed it in a hot box, the numbers now work like this:
9.92 times 1 / 70, which works out to 0.1417 ignored units.
The equation doesn't balance. 1.87 does not equal 0.1417, regardless of the units
You'd need a LOT more air, a lot LESS vacuum (when was a vacuum leak a good thing?)
Ok Greg, I have no idea what you are doing here, either you've gone off on a tangent or you will need to explain further. I only said pressure is irrelevant because it is unchanged; and when both sides of the equation stays at the same value I can leave it out of the maths. A hot air box changes temperature of the air, the air always stays at atmospheric pressure- same pressure. I see that you have done the calculations with vacuum figures, I don't think what happens after the butterfly is relevant - but even if it could be argued; Where did you get the vacuum values from? If you are just going to assume values then you can pretend the density of air changes to whatever you want by "guessing" whatever vacuum values you want.
Also you must use Kelvin, because Kelvin is the zero point for temperature. Zero degrees Kelvin is the point at which zero heat exists. Your calculation is not correct when using degrees celcius, Nor with the guessed vacuum values. My calculation was correct.
More science: Vapour point and Boiling Point are NOT the same thing. Read for yourself Note: it mentions pressures.
Again Greg. You don't know this about me but I know a lot about this field. Not saying that I can't learn some new application of it. I red the link you put up. But what is vapor point? I googled the term vapor point and it searched for vapor pressure and I did not find any definition of vapor point. Boiling point of water is 100 degrees C, So what temp is vapor point?
You have mis-read (or misinterpreted) what I said about intercoolers. I said, "Intercoolers are used to cool the increased air charge from the turbo." Jamming more air into a container of a fixed size will change its pressure, because the Mass of air is increasing, so it's temperature must react to keep another equation balanced...and again, units matter here are we talking kilos or litres or what?
Again Greg, I am not sure what you are saying here. Please clarify. Your previous thread was clear that you do not want to try hot air induction due to the loss of density. Example you gave was turbo motors needing to intercool to gain density. I just pointed out that a lot of turbos dont worry about intercooling. Intercooling for density increase is only part of what the intercooler does for the motor. Therefore the intermittent use of intercoolers on turbo applications doesn't prove hot air induction will kill an engines performance. There will be a loss, which MUST be compared to the gain (better vaporisation) before an outcome can be stated.
Don't change your engine - change your mind. Please. I'm trying to help you here. Start by looking at your throttle position sensor.
it has to agree with what the computer has been ingrained with (before we can teach it a new normal for the groove), and by doing what I suspect because of the IAC mod you've made, they are out of whack, and that'll make the oxygen sensor work in not-right ways...
I don't plan to change my engine and Im happy to change my mind and try any mod you recommend following any good experience you have had. I think I have ruled out ; by my comments any need to worry further about the TPS causing my motor to run rich.
Thankyou for your thoughts and I look forward to further ideas with a hopeful economy increase on this car.
Best regards, Neil
