87' 302/2wd/18-19/23MPG. When I read MPG's like yours, it makes me sad. It doesn't have to be that way, unless your compression is off the chart (and I don't mean the upper portion of the chart!)

 

Had it since 98, never gotten more than 13 city, 16 highway.
Lifted er up 4" and threw on 33"s and that dropped me down to about 10-11.
Anyone have suggestions?
LOL

 

Every body seems to be leaving it up to me (or aren't that bored yet) to point out the obvious, so here goes: There are no possible MPG"s that can be obtained while "Parked". "0" cannot be fractionated. Therefore, your mileage while parked must have remained the same. "dewman" got me started on this logical kinda type stuff.

 

In bicycle racing, it has been determined that the weight of the wheel & tire (not frame weight) has the greatest effect on expenditure of energy, so your tire & wheel weight would greatly figure into it. More so, while reaching cruise speed. Less so, in maintaining that speed. At that point centrifugal force comes into play also. Aerodynamic is an obvious player also. I'd have to start w/ your compression test results (dry & wet) to determine a ballpark as to what you should reasonably expect for MPG's! Of course, any mods would also figure in. Original engine displacement rating doesn't guarantee the same transfer of energy to the wheels now. In regards to the calamity the guy (WC53) you keep quoting is experiencing, I've seen "kits" advertised on late night T.V. that claim they can cure people like that. He has my condolences! He should remember, "It's not the Blah, Blah, Blah ,.. It's the Yada, Yada, Yada! And Stroker engines are a figment of the imagination.

 

hey, thanks alot for the input. makes a lot of sense. Went back and tested various sensors again. The ECT resistance check was good for both hot and cold conditions. Yes, correct signal voltage going to MAP, but when plugged in, KOEO, MAP output voltage was only 2.5 V. Book says it is to be 5.0. Also, the IAC or BPA-ISC resistance check was good, but signal votage to the sensor was 12.6 volts. Book says to be 10.5 Volts . Did perform KOER test, codes 116,117,172 &412. I figure the 116 & 117 were there because I ran engine with the ECT unplugged prior to the resistance check for the hot scale. Also, at idle, engine seems to be "hunting" or "porpoiseing" in rpm, (up and down, up and down).

 

I have a 94 4x4 with 5" lift and 35's WITH 4:56 gears, GT-40 heads, ported and polished, JBA shorties, and edlebrock mani. On average I get about 12 MPG city.

 

I was gonna say that 50% was pretty good because at idle you are going 0 MPG... burning fuel and going nowhere...