damn gas mileage

[jaidedeye]

well after my t-5 swap it seems like my gas mileage is crap. i installed a new fuel filter, plugs,and set the timing to 14 degrees. so whats the deal? my gas guage says i have gone 37 miles on 1/4 tank. whats the deal? i have only driven the car back and forth to work wich is only like 4 miles each way.

so, whats the deal? the gas guage jumps around when i drive....maybe a bad sending unit for the guage? i have noticed when my car is on E it will only take like 12.5 gallons on a fill up.....i checked the plugs to see if i was running rich..well the plugs look nice and clean and the porcelin is still bright white.....so what gives?

 

[jaidedeye]

ttt

 

[jrichker]

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

 

[1985MustangGt]

Subscribing to this one... what if your as lucky as me and dont have a comp? I have even put it on the scope and tuned it. Still same old crap.

 

[Grn92LX]

Did you connect the neutral safety switch up?

 

[jaidedeye]

Did you connect the neutral safety switch up?

what does that have to do with fuel economy?

i bypassed it with a push button starter

 

[Grn92LX]

what does that have to do with fuel economy?

i bypassed it with a push button starter

It caused me some horrific cold start idle problems not having it connected. It was just a thought

 

[HISSIN50]

my gas guage says i have gone 37 miles on 1/4 tank. whats the deal? i have only driven the car back and forth to work wich is only like 4 miles each way.

one needs to be more scientific. you are doing short trips (open loop) and interpolating the gas gauge. noting milage after filling up and calculating it is the only way to figure out what gives. some longer drives might help too.

good luck.

 

[jaidedeye]

It caused me some horrific cold start idle problems not having it connected. It was just a thought

how did you figure it out? cant i just take the two wires in the plug under the car and splice them together?

did it cause you fuel economy to suck or just idle issues? my car idles great. dead on at 900 rpm with my f-cam

 

[Grn92LX]

I went under the car and I happened to see that it wasn't connected. Once I connected it, my cold start idle improved a LOT. I still don't know how that is, but it did fix that cold start idle I was having. Im not even sure about if it helped the gas mileage. I've driven my car once in the past month and it was basically a quick drive around town and I came home. I took it for a test drive after putting it all back together and then came home and parked it and put the cover back on