Fuel

[DarkKnight]

Hi there, Ok, i know im posting alot im just a bit quiscked atm,

Here's my question


How much will these componet's help me for mpg?

o2 sensor

Exsaust, prob stock for now

And a Electric fan setup

and sometime off in the distance, Header's and dual straight pipe's

Im just wanting what will get me what type of mpg. like o2 sensor will raise me to 10mpg ect.

O and umm at the moment my mpg has droped agine. i guess due to my bipass for the cat's ( AKA the big ass hole's i cut )
But atm im not sure im even getting a mille to the gallon,


This i came up with i put 10$ in it a whille ago came back from the store 1.2 milles

Went back a min ago and came back, 2.4 milles

the 10$ gave me about a quarter of a tank

After i came back the second time. im back on E...


Any how thanks guys for any info, if your still unfamilure with what im asking just let me know, )


Thanks agine,

D.K.

[85crownHPP]

if you went 2.4 miles and lost a 1/4 tank, you have a major fuel leak or something.

No one can tell you how much your MPG will increse with those parts, becuase no one knows what the problem is.

fill the tank up ALL THE WAY - observe your mileage, then fill up all the way again to get an accurate mpg reading. Also chech for gas leaks during this.

1/4 tank in 2.4 miles is inconcievable. either your gauge is very wrong, there is a leak.... or something.

The last idea that came to my head is this - if you see droplets of fuel comeing out of your injector, maybe the o-rings are leaking and letting fuel run down the injector. Try out one of those extre CFI units you pulled

[87mefull]

No backpressure from the lack of the exhaust system will kill your gas mileage. Basically you are running open headers, 2-4 mpg is not unrealistic and you cut the performance almost in half also. Excessive backpressure kills performance and causes overheating (clogged cats for example) but not enough or none kills low end torque and gas mileage. Throws off the 02 readings in some cars but I don't know if it will affect you car enough.

Have to start simple first with the exhaust system, its doing the most harm right now. Get that fixed first as its doing the most harm and is a huge fire risk (read other thread). Spend money and time fixing other problems later and we will be glad to help you.

I can probably guess you have some vacuum leaks still since in older pics the smog pump was removed and the egr valve was changed. Look into getting a ford OBD I trouble code scanner, you car can be scanned for codes just like any other 83-91 box, 92+ are OBD 2. I have seen them go for as low as $15 on ebay and are probably one of the most useful tools for diagonising problems on a computer-controlled EFI vehicle. It also makes it alot easier for the gurus on this site to help you with your problems. Example: code 43 (4 flashes, pause, 3 flashes) means oxygen sensor indicates a lean condition at WOT. Doesn't mean the O2 sensor is faulty, this code was a common code I recieved in my car. Turned out the egr valve wasn't closing, changed it, and I get 16city/23 highway now and no longer have performance problems. Not saying you have an egr problem, just that the right tools make solving problems simple, which keeps more money in your pocket.

[85crownHPP]

the holes he made arent anywhere near free flowing so some backpressure is still there, and hes even sort-off patched them up. that or even leaving the brake booster unplugged should not cause 3mpg though. Something stranger than that is going on....

[DarkKnight]

Well one of my pacthes came completley off now... Boo... I got to thinking about this And the bad gas millage started around the time i changed my fuel filter. But i see no leaks... or i didnt, ill take that plate back off and fill for preasure.


I got a code scaner mang. :-D But i can only run KoEo I cant run the koer test it just sit's there and does squat.. But ill run the codes agine. Weired ass engine and cfi i got... Would be a great car if never had been ran by a "Dee Dee Dee"


Thanks mang's
Dark


O yea, Pete mang, is till cant do that test with the millage, due to umm. my odemoter is still broke... I read my Shopmanual. And i was doing evreything right but i guess either my cable is two short or it's caught on something back there, case i cant pull my Speedomoter out at all. it moves about this much - and thats it.:-/

Thanks agine mang's

[Blaze86Vic]

2.4miles on 1/4 tank would be about .5mpg.....not believable. Either the gauge is wrong (most likely, and acceptable) or you are pouring a stream of gas.

[DarkKnight]

Humm, im betting my gauge is wrong then..., Help me do the math, i wasd on e spent 8.00cent's gas atm is 2.99 a gallon. Now i might be able to do this. correctley but im not sure how big/small are fuel tank's are ) but 8$'s put me right under a quarter of a tank. from the e line.


Thank's

d.k.


:: Edit ::: O yea, and im fixing to go pull codes or at least try. :-D

[interceptor1985]

we had clogged muffles on the cop car so we cut them off and put some pipe in place but the pipes are too small so we still have back presser but we got better gas mileage for it I'm not good at math neither how many times do you have to fill up?

[DarkKnight]

I just put 10$ more into her... thats 30 dollars in 4 times of cranking her. and going to the store ) Eh wait no :-<...


Dark

[Blaze86Vic]

The problem is the gauges are not linear. 1/4 tank on the gauge is more than likey when you actually have 1/8 or 3/8 of a tank. The only way to guess mileage is to do full tanks. That way when you fill it back up untill the pump automaticaly stops, you can see what you put in, and that is what you used.

[mrltd]

Get the codes fixed and the car running right before doing any mods.

[DarkKnight]

I agree MrLtd, thats the reasson i havent done a bunch allready, i so badly want to though....,


And that really makes since Blaze :-D I still wont be able to tell how many milles i go. But Hey! :-D

Umm, so how big are our tanks?

[87mefull]

I'm pretty sure you have a 16 gallon tank, which was standard on a base crown vic for 1985. Some cars were optioned with 18 gallon tanks, but more often I seen them in Lincolns. Wagons came standard with 18 gallon tanks.

Like blaze said, your gauge is probably inaccurate but it seems to be common with these cars. My gauge is not accurate below a 1/4 tank, mainly because of the way the gas tanks are skewed and that the sender doesn't work well when its low. The tanks are skewed to hold 10-11 gallons in the top half of the tank and 5-6 gallons in the lower half from what I heard (not exactly sure) for a 16 gallon tank. Common mistake is that people think they get substantially better gas mileage at a half tank or above vs. below it.

In other words, my gas gauge quickly drops usually when I reach a quarter tank even while getting 20mpg. I know I have more gas than it reads though, even if the low fuel light comes on, but its usually only 1-2 gallons.

Work on getting the other problems fixed first though, gas mileage will be much better. Fill it up then and record your gas mileage.

[DarkKnight]

Cool, so prob. faulty enginering back in the 80's aka poor design. )


Thanks for the head's up on that one ill get to fixing the other stuff.