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Im getting 5 MPG !!! Whats Wrong???

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Old Aug 24, 2004 | 12:43 AM
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Exclamation Im getting 5 MPG !!! Whats Wrong???

Im getting around 5 mmiles per gallon ( the FC has 18 gallons ryt??) and theres no sign of leaks on the ground where i park my car everyday...
Whats can be the problem???
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Old Aug 24, 2004 | 12:47 AM
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dirty injectors? need full tune up? clogged to hell exhaust? dirty sick intake? it could be lots of things or a combination
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Old Aug 24, 2004 | 12:56 AM
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it's all about the o2 sensor...get a new one...I had about the same problem and it changed from like 6-8 MPG to like 15-20
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Old Aug 24, 2004 | 01:05 AM
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Originally Posted by chiefnobum
it's all about the o2 sensor...get a new one...I had about the same problem and it changed from like 6-8 MPG to like 15-20
o2 sensors are cheap and relatively easy to replace. Give it a shot, you might be surprised.
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Old Aug 24, 2004 | 01:10 AM
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ok guys.....thanks.....im going to prey this works....
So TOMORROW im going to :
Change Engine Oil
Transmission oil
Take a look at the air filter ( can i just put on my Apexi intake?)
Try and buy/ install a new o2 sensor
Change Spark Plugs
Anything else i need to do???
'
How do i clean injectors ( arnt those spark plugs?)
How do i check if i have a clogged exaust???
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Old Aug 24, 2004 | 01:22 AM
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From: Freaking Poland!!
Injectors are not spark plugs. Injectors inject fuel into the intake and the spark plugs ignite the air/fuel mixture inside the combustion chamber.

You clean the injectors by sending them off and having it professionally done. It's the best way and will cost you around $15 shipped for all 4.

If you cats are clogged they'll usually glow red after driving awhile.
EDIT: Oh yeah, you're engine will also bog down and loose power when it shouldn't....

Good luck on changing the tranny oil, but yourself some kind of Oil squirter with a long hose. The bolt is hard to get to.
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Old Aug 24, 2004 | 01:42 AM
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Injectors are most certainly not spark plugs, rather they are what introduce fuel to the air being sucked in by your motor, sorta like a carburator, but usually much more complicated and computer controlled. A clean fuel injector sprays fuel much like a misting spray bottle does, atomizing as much of the fuel as possible which equates to a more even and complete burn. As injectors get dirty the spray becomes less and less of a spray and more of a drizzle, which is harder to mix with the air, hurting performance. An engine will try and correct this somewhat by attempting to add more fuel, but since it wont atomize properly all that happens is your fuel mileage goes down the drain, as for cleaning injectors, you can find an additive for your gas prety much anywhere with a name like "fuel injector cleaner" prety easy to find, you simply add it to your gas and as u drive it slowly scrubs the injectors, however it was designed for piston engines and i dont know personally if it will harm a rotary, so before u go out and get some of that, maybe someone more knowledgable will come along with some solid facts on "injector cleaner". Anyways good luck, i hope that you can get this all sorted out
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Old Aug 24, 2004 | 02:04 AM
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thanks guys.... i hope i get out of this mess ....i have more problems than this.....clutch problem, shifting problem....sigh..... i think i should bring it to a shop
+
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Old Aug 24, 2004 | 02:21 AM
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i could see how a clutch problem would affect your shifting problem
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Old Aug 24, 2004 | 03:18 AM
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lol "easy to replace". Im sorry, but I BEG to differ on that one.

The o2 sensor 'should' be easy to replace, I'll give you that. But when its been in the header for over 10 ******* years, it sure isn't 'easy' to replace.
First off, trying to get enoughe leverage in that small amount of space is hard enoughe, its double hard when the ******* sensor is siezed in the threads!
First I tried for a couple days trying to get that ******* thing out, I tried adding on pipes to the end of my ratchet for more levarage when I finally got some movement! I was so happy and turned more and then 'snap', my extension twisted in half! lol
So I got my dad to bring home a much larger ratchet from work, a really good one, I popped it on and put more piping on the end, even with that kind of leverage, it didn't ******* budge! christ!
So finally I got my dad out there with me and it was so ******* funny, here's this old guy, smoke in his mouth with a cap and sunglasses on, sitting in the engine bay like a little kid in a sandbox trying to find a better position for leverage!
lol he finally gets in this squatting position and starts tuggin, the car is totally rocking back and forth, back and forth, and finally you hear that wonderfull squeel of success!
I handled it from there and my dad went back inside sort of limping! it was so funny.

But yea bought a bosch 60$cndn sensor and it made a big difference, exhaust didn't stink as much and yes I got better mpg.
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Old Aug 24, 2004 | 03:44 AM
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I know I have to replace mine, getting like 16mpg right now no matter what.
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Old Aug 24, 2004 | 03:54 AM
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Well just make sure you get yourself a o2 sensor socket and some pipes heh..
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Old Aug 24, 2004 | 04:39 AM
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A bad O2 sensor is not going to cause the car to go from normal gas mileage to 5! The car even runs fine with it disconnected. How will a faulty one make it get this far off? It might make a small difference but not 5. I'd check to see if the cats are clogged. I'd also check to see if all of the plugs are firing. Check your timing. Are your double throttle plates opening (assuming you still have them). How does the car run otherwise? Maybe the afm is having issues. Maybe the ecu is messed up. There are too many things it could be. We need to know some other symptoms and then have you start to go down the line checking things. I'll tell you the one thing is definitely isn't though and that is the O2 sensor. For proof just disconnect it and drive around. The car runs fine without one. You'll still get 5 mpg. Are you sure there isn't a small problem elsewhere and you aren't just flooring it everywhere you go?!
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Old Aug 24, 2004 | 05:09 AM
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Originally Posted by rotarygod
A bad O2 sensor is not going to cause the car to go from normal gas mileage to 5! The car even runs fine with it disconnected. How will a faulty one make it get this far off?

well he's right about that. the ecu checks the o2 sensor during low load low throttle cruising type driving to see if it can go into a closed loop mode and lean out your mix. i drove mostly city driving with no o2 hooked up for a month or so and lost maybe 1-2mpg at most per tank. you've got other problems. full tuneup is in order. also i suggest turning down the boost to a setting that gets you under 500 hp and see if your mpg goes back up
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Old Aug 24, 2004 | 07:57 AM
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Originally Posted by Parastie
o2 sensors are cheap and relatively easy to replace. Give it a shot, you might be surprised.
Where do you get yours? Mine are $50, or is that cheap?
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Old Aug 24, 2004 | 09:45 AM
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$50 is way too much. Theres a great import performance shop near me that sells them for $25.

-Joe
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Old Aug 24, 2004 | 09:53 AM
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Advance autoparts sells the bosch generic o2 sensor for our car that you splice into the wire for about 13 dollars. you can get one with the connector so you dont have to splice, for about 25
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Old Aug 24, 2004 | 10:04 AM
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timing man


back when my car's timing was off really bad ,... i was getting about 120 miles per tank ..
make sure your timing is straight ... you'll notice an increase
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Old Aug 25, 2004 | 04:06 PM
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Guys....i went to an auto shop 2day...i asked the guy to check wat u guys asked for.......the guy...he told me my car was fine......i said " No, Way!!!" ...he said "your engine is very smooth, even smoother than mine, i dont see how u get 5 MPG...try adding 91 premium"

Should i try premium???
Anything u think he missed???
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Old Aug 25, 2004 | 04:32 PM
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91 premium isn't gonna fix 5mpg... Maybe you'll get 6.
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Old Aug 25, 2004 | 04:37 PM
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danm.....so what should i do now???
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Old Aug 25, 2004 | 04:42 PM
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if you have not changed the 02 yet, then do so. Not sure if this is the solution to your problem, but since they are relatively inexpensive, i would do so.
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Old Aug 25, 2004 | 05:13 PM
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Yea get the o2 replaced first. Then take it to someone else! what a bum, he just doesn't want to work today thats what im thinking.

But yea timing and the cat could have alot to do with it.
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Old Aug 25, 2004 | 05:18 PM
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when you turn the car on, does it sound like its got a small animal inside it? does it even run smooth? does it smell like fuel real bad when you turn it off? bcuz fuel leaks suck ***...
When you turn the key to the "on" position does gas shoot out of the fuel lines? that happened to me once
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Old Aug 25, 2004 | 06:11 PM
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nah...none of that
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