tbird is doing 10MPG HELP!!!!!

Topic: tbird is doing 10MPG HELP!!!!! (Read 2330 times) previous topic - next topic

tbird is doing 10MPG HELP!!!!!

June 07, 2007, 07:01:18 PM

Guys my 5.0 t bird is using way too much gas. The 5.0 is hardly modded. Its had a tune up. My mods are bbk headers , h pipe, magnaflow exhast, bbk intake. Shouldnt my 5.0 be doing 28 mpg high way and 17 mpg city???Can someone let me kno what it could be??? injecters maybe?

tbird is doing 10MPG HELP!!!!!

Reply #1 – June 07, 2007, 07:33:37 PM

All that madd racin.

tbird is doing 10MPG HELP!!!!!

Reply #2 – June 07, 2007, 08:25:28 PM

Oh man. Nah i dont do "madd" racing . Im serious what could it be cause its causing me alot of money on gas.

tbird is doing 10MPG HELP!!!!!

Reply #3 – June 07, 2007, 08:56:24 PM

check your o2 sensors, usually when they go back they stick giving either a way rich or way lean reading... way lean in your case

tbird is doing 10MPG HELP!!!!!

Reply #4 – June 08, 2007, 02:56:47 AM

Sounds like you have the engine modified beyond what the speed density can handle, and it has gone into closed-loop default and running rich. Could also easily be the O2 sensors causing it to go full rich.

tbird is doing 10MPG HELP!!!!!

Reply #5 – June 08, 2007, 03:02:51 AM

the 02 sensors are brand new motor craft

tbird is doing 10MPG HELP!!!!!

Reply #6 – June 08, 2007, 04:23:26 AM

i got lots more mods and i still get like 22 city and close to 29 highway.

i don't know what to tell you

tbird is doing 10MPG HELP!!!!!

Reply #7 – June 08, 2007, 07:25:22 AM

You might have a leaking fuel injector. Here's how to test them:

"Remove the injectors, get a 9volt battery and two test leads with alligator clips (unless you saved an injector connector at some point). Get a can of gum out, the tube fits right into the injector input port. Push the tube down into the little hole and squirt. If it comes out the other end, it's sticking open. If it doesn't come out the other end unless you power up the injector with the battery, then it's ok. You can get an idea of spray pattern with this test also." That was from the Corral.

I haven't tried it myself yet but I need to because my mileage sucks too. I just got 11.9 on my last tank.

tbird is doing 10MPG HELP!!!!!

Reply #8 – June 08, 2007, 08:32:21 AM

I had the same problem 3 years ago when I first did the HO swap in my old T-bird(it sat for a year)...it was the most frustrating thing in the world...an $8 fuel filter later and good fuel mileage was restored, it's a cheap fix and if it doesn't cure your ailment, it's still money well spent.

Good luck,
Don

tbird is doing 10MPG HELP!!!!!

Reply #9 – June 08, 2007, 09:40:09 AM

Quote from: Prototype Services

Sounds like you have the engine modified beyond what the speed density can handle, and it has gone into closed-loop default and running rich.

You're kidding, right? Go to http://www.50tech.com and read around a little. You'll see what kind of combos can be run on the Fordd EEC-IV SD computer. All his mods are exhaust and intake related, absolutely stock internals. THe SO SD computer can handle that and quite a bit more even before he'll NEED an adjustable fuel pressure regulator. That being said IMHO it should be one of the first mods accomplished on an EEC-IV or EEC-V equipped car with a return style fuel system.

Run codes and tell us what you get.

tbird is doing 10MPG HELP!!!!!

Reply #10 – June 08, 2007, 06:14:08 PM

I'm running a .533 lift cam and GT-40P heads with a Mark VII SD computer with virtually no problems. Once in a great while it has a bit of idle surge but that's usually when I get on it and stop right away:hick: .

tbird is doing 10MPG HELP!!!!!

Reply #11 – June 08, 2007, 07:59:33 PM

i think its the injectors cuase i changed teh fuel filter and teh car has a tune up. When i change dteh iifters i changed all gaskets on top and hoses as well. And yes teh engine is really stock so it shouldnt be drinking so much gas. . If i get new injectors I need 14lbs injectors correct??

tbird is doing 10MPG HELP!!!!!

Reply #12 – June 08, 2007, 09:55:25 PM

also do an injector balance test,,, see my diy link above my sig. You dont have to pull injectors for this test,, just unhook them one at a time.

Im surprised no one has ask that you pull the codes,,, do so before you tear into anything.

tbird is doing 10MPG HELP!!!!!

Reply #13 – June 08, 2007, 11:53:15 PM

Quote

Im surprised no one has ask that you pull the codes,,,

See post #10:D

tbird is doing 10MPG HELP!!!!!

Reply #14 – June 09, 2007, 12:01:10 AM

I got a set of explorer injecters if ya need