Fuel consumption?

[larry33kc]

I have finally been able to get the car out and get some miles on it, and it is getting horrible fuel mileage. It's getting around 9-12 to the gallon. I know the IAT sensor is acting up and I have a new one to put in. I had the laptop plugged in and was noticing it was going from 90-270 non stop, and the car would run bad as it went in the 200+ in temp.

I had the fuel pressure set at 55#'s line off. I now have it lowered to 45#'s line off with hope of trying to get better milage.

My question is how much do these things affect fuel mileage? What else could be the problem for such bad mileage?

I know that I'm not going to get 30mpg with my setup but it should be better than this.

 

[John Larkin]

Why did you have the fuel pressure so high? It's still too high, a little anyhow. Most chips work best at about 42 line off. I would say that any sensor that is acting wacky is suspect. Throw out your scanmaster readings from each input.

 

[larry33kc]

I was told that E85 like a higher fuel pressure setting, I don't have a scanmaster I run a Bigstuff3 setup.

 

[John Larkin]

Oh. I really changed nothing when I converted to E85 other than bought an appropriate chip. E85 requires about 30% more fuel to operate with and air/fuel ratios are different than gasoline. I don't think anything else is different. Might post in the E85 forum and see if anyone has any setup suggestions for your engine management system. I didn't even read your signature, you have a hefty drivetrain there.

 

[Jack Parl]

Using E85 in most vehicles will drop milage apprx. 20%. A gal of E85 doesn't have the energy content of a gal of gas. Will let the professor types explain. The whole push to Ethanol blend and E85 amounts to huge subsidy to corp. corn farmers.It does run cooler and at higher compression. Did I get it right guys???

IllhaveaV6

 

[larry33kc]

Yes I know it uses more fuel running E85. But if I figure at an average 10.5 mpg and X's that by 20% that's what 12.6 mpg. That's still lousy. I would think it would do better than that.