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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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i feel like my mileage should be better....

  • Thread starter Thread starter Foxfan88
  • Start date Start date May 29, 2005
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Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
May 29, 2005
#1
  • May 29, 2005
  • #1
ok my stuffs in the sig, the motor is stock besides headers and aftermarket ignition and harness.
I've calculated 10 mpg with 87 octane, would this increase with higher octane or something, if it would i would think it would be very minimal.

What are the little fine tuning things i could try to see if i get better mileage, i am thinking 10 mpg is a little strange for a pretty close to stock car.

Any help appreciated.
 

70lightning

New Member
Mar 30, 2005
205
0
0
in the basement makin stuff
May 29, 2005
#2
  • May 29, 2005
  • #2
Have you sorted out your timing and temp issues, becuase these can both affect mileage.
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
May 29, 2005
#3
  • May 29, 2005
  • #3
My timing is at a stock 10 BTDC, i have a temp issue???
 
G

GT89Mustang

New Member
Mar 31, 2005
0
0
0
Monmouth County, NJ
May 29, 2005
#4
  • May 29, 2005
  • #4
When was the last time you did a full tune up on the car?
 
E

exhausted

Founding Member
Feb 13, 2002
122
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0
Spain
May 29, 2005
#5
  • May 29, 2005
  • #5
19 mpg on every tank on my 86gt. Most of the miles are highway though.
 
O

oohsoobad2

Banned
Dec 17, 2004
127
0
0
May 29, 2005
#6
  • May 29, 2005
  • #6
Id look into the basics such as plugs, wires cap and rotor or fuel filter. 5.0's arent really the best MPG, but 10 MPG seems excessive.
 

spyne

New Member
Dec 13, 2004
78
0
0
Fairfax, VA
May 29, 2005
#7
  • May 29, 2005
  • #7
I'm getting about 17 mpg in my 154K vert with an auto tranny. Are you sure you don't have 4.10's in the rear or something else in the drive line that might have been changed before you got the car?
 
M

mikeflys1

Founding Member
Aug 27, 2002
217
1
0
CT
May 29, 2005
#8
  • May 29, 2005
  • #8
Yeah with like all city driving/beating the poop out of it i get like 17-18mpg. I'd start with a tune up and probably o2 sensors.
 

sunil6784

Member
Mar 31, 2005
620
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18
Boston, MA
May 29, 2005
#9
  • May 29, 2005
  • #9
I did a tune up on my car...plugs, wires, cap, rotor, fuel filter...and my mileage went up almost 4 mpg. Next up will be O2 sensors.
 
M

Mark89coupe

Member
Apr 5, 2005
206
0
16
May 29, 2005
#10
  • May 29, 2005
  • #10
I did 30 mpg a few weeks ago all highway miles.
I did a tune up in November last year. I use 87 octane. I also had a bad tranny in the car. 70 mph on the highway. I havent touched the timing in a few years.
I had found a thread on the forum and tried it.- Clean the mass air wire, IAC valve, take the egr off and clean it, put seafoam in the gas tank and throught the brake booster line. It worked miracles for my car.
 

70lightning

New Member
Mar 30, 2005
205
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0
in the basement makin stuff
May 29, 2005
#11
  • May 29, 2005
  • #11
Foxfan88 said:
My timing is at a stock 10 BTDC, i have a temp issue???
Click to expand...
Foxfan88 said:
Ok my car ticks under a load, like when i give it some gas. But when the car is cool and i baby it its ok. Only pings when i start going fast.
Well yesterday i was hanging out with my friend, he had his moms crown vic, we went and had some fun.

Well this has happened before, but when i "abuse" or just really hard on my car (trying to do burnouts) it starts KNOCKING(like an actual knock) like hard core, its always there, really loud, it diminishes as your easier on the car and the engine cools.

So is this spark knock, since the hot engine will ignite the gas easier before the spark? I have 89 octane in now. I dont have a timing light, would buying one be wise? How useful are they later on?

BTW, the vic pulled a massive donut, they are pretty damn powerful.

ALSO, my temp guage doesnt work, so i cant tell... well how hot does the motor get, mines gets to where you can feel the heat off of it, like if you were cold it could warm you.

Is it just v8s get hot??? since they are bigger...
Click to expand...
 

70lightning

New Member
Mar 30, 2005
205
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0
in the basement makin stuff
May 29, 2005
#12
  • May 29, 2005
  • #12
I still think you have some issues to sort out if you are tryin to do burnouts but not able too, and a crown vic does do-nuts better than your mustang.
 

cjman15

Banned
Apr 15, 2004
1,009
0
0
Fairfield, PA
May 29, 2005
#13
  • May 29, 2005
  • #13
Yeah, definately do a FULL tune-up... as well as change tha o2 sensors... if you don't see a big improvement, something is wrong
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
May 30, 2005
#14
  • May 30, 2005
  • #14
It might be my timing, i put gas in it as soon as i figured out how to do it.
Havent checked mileage yet.

Well the car has accel wire, msd coil, cap and probably rotor, has an aftermarket distributor. So the guy before me did some stuff.

I'm sure the gears are stock 2.73s, i did the driveshaft rotation technique

So should i just tune up myself???
I've heard to term "performance tune" can someone elaborate???

Also, i can burnout, i just dont like the one tire roasting them, i'm more interested in spinning both....
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 30, 2005
#15
  • May 30, 2005
  • #15
I doubt timing will make an appreciable difference. running retarded timing can cause bad milage (hence why cars advance timing through the roof at speed; not including provisions for EGR).

FWIW, i ran locked out timing (22*) on the 94 and it made less than 1 mpg difference with in-town milage.

good luck.
 
D

Dtowncats

New Member
Jun 2, 2003
340
0
0
York, PA
May 30, 2005
#16
  • May 30, 2005
  • #16
You definitely need a tuned up! Before I changed my fuel filter I was getting 13 mpg with 2.73 rear gears and mostly highway driving. Now I am around 15.5 mpg since I changed it. Gotta change the o2 sensors now!
 
I

Insane3D

New Member
Jul 21, 2004
310
0
0
May 30, 2005
#17
  • May 30, 2005
  • #17
I just put in new O2's in my '92 GT when I put in the FRPP headers and Bassani OR X. I was getting about 70 miles to the 1/2 tank point, and now I'm getting ~125 to the same point.

O2's are fairly cheap @ $39 ea, and you would be surprised how well they affect mileage..
 
E

exhausted

Founding Member
Feb 13, 2002
122
0
0
Spain
May 30, 2005
#18
  • May 30, 2005
  • #18
Did someone above say 30mpg with a 5.0. GMAFB!!
 
M

Mark89coupe

Member
Apr 5, 2005
206
0
16
May 30, 2005
#19
  • May 30, 2005
  • #19
exhausted said:
Did someone above say 30mpg with a 5.0. GMAFB!!
Click to expand...
Yep. I filled up got on the hwy then when I got off I filled it again. I almost sharted my drawers after I did the math.
What does GMAFB stand for?
 
N

nickg42oz

Founding Member
Dec 16, 2000
358
0
16
New Orleans, LA
May 30, 2005
#20
  • May 30, 2005
  • #20
I'm getting about 8mpg. Its running rich though, some sensor issues
 
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