mpg/running rich

[Dash71121]

just bought my b2 with the 5.0L efi already swapped in it. i just ran my first tank of gas through it and recieved 14mpg. i replaced the plugs, wires, cap and rotor, changed the oil, and cleaned the filter right when i got it. is 14-15mpg what i should expect from the 5.0/aod combo? it is also running very rich and i dont really know where to start with that.

the miles were probably 50/50 highway/city. didnt get on it but only a few times.

thanks, dylan

 

[Snal]

I've still got a 2.5L in mine and I wanna do the same swap but I dont wanna run into the same dilemma but In my opinion I really think thats just how the V8 runs. I mean it's efi so you cant adjust how much fuel goes in and if you just maintenanced it and it's still the same I would think thats just how much gas it takes. You could change the gears in your differential and that could help along with tire size but those arent the cheapest solutions

 

[Dash71121]

haha it definitely nice not being underpowered now though.. i had a samurai with the 1.3L for a long time and i also have my 79 bronco with the gutless 351m and 37's, even with the 4.88 gears it was still a dog

 

[chazzone]

If its running rich, then you should definitely be able to increase mileage by getting it running properly.

What kind of fuel system does it have? Is it carbed or EFI?

If it's EFI, time to get a digital multi-meter and a manual from the donor vehicle, and start diagnosing.

 

[kimcrwbr1]

If it has the complete harness run the codes it might be running in limp mode with a set timing advance are all the sensors hooked up the computer defaults to preset values without the proper inputs IAT, MAP, TPS, OXY, MAF, ECT, EGR position sensor, whatever the system is designed to have you need to get working properly. If you can pull codes fix the first codes first as a faulty part can throw other codes too and reset the computer every time to change something by unplugging the battery for 15 mins and then run it at medium speeds in all gears till it gets good and warm before running the codes again. once you get a pass code you should be good. Make sure you reset the comp (disconnect the batt) and erase the memory regular so your not showing false codes and replaceing good parts GL

 

[baddad457]

just bought my b2 with the 5.0L efi already swapped in it. i just ran my first tank of gas through it and recieved 14mpg. i replaced the plugs, wires, cap and rotor, changed the oil, and cleaned the filter right when i got it. is 14-15mpg what i should expect from the 5.0/aod combo? it is also running very rich and i dont really know where to start with that.

the miles were probably 50/50 highway/city. didnt get on it but only a few times.

thanks, dylan

14-15 is about what I get with a carbed roller 5.0. What transmission, rearend and tires are you runnning? How often are you planting your right foot on the floor ? What fuel are you running ?

 

[Dash71121]

it is an efi motor, it has a mustang intake manifold and injection, idk what the block is out of. transmission is an aod, not sure on the rearend gears, tires are 31's. i will try and pull the codes at work today.

another thing to mention is that the check engine light will come on once in a while, but hwne i shut the vehicle off it goes away.

 

[kimcrwbr1]

Go through the harness and see if all the grounds are metal to metal and yea pulling the codes will give you an idea on the light kinna sounds like a loose connection so pull all the connectors apart clean them with elect cleaner and give them a shot of dielectric and make sure the pins are all pushed in. while your doing that disconnect the battery to reset the computer hard faults and then erase the memory. Then get it good and warm running thru the gears at medium speeds to set the new values then test again. Both KOEO and KOER anxious to hear the results

 

[Teddyzee]

Get it running right, pull the codes, see if anything comes up. Depending on the gearing, 31's, auto, and 4x4, that may be all you get.

I get mid 20's with mine on the highway. It's 2 wheel drive, EFI 5.0 HO

 

[Dash71121]

well i cannot find where to plug the obd2 scanner into... i cant even find the computer on this thing, it has both the under hood and under dash fuse panels, but cant find the damned computer lol

 

[baddad457]

The computer should be behind the passenger side kick panel.

 

[Dash71121]

ok found the computer, still cant find the port to plug the scanner into though... i'll have to go through the wiring this weekend if i can, the gun show is also this weekend lol

 

[kimcrwbr1]

It should be somewhere close to the power distribution box under the hood but I dont know much about OBD-2 is it still considered EEC-IV