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- Protege5 2003
Possibly it is misfiring? If the car misfires the fuel economy will suffer. Could be iffy wires or a failing coil pack.
My car had an episode with bad wires and while it never misfired badly enough to throw a CEL, it did stumble a bit in first gear, the fuel economy went down about 10-20%, and sometimes at idle in neutral it would take brief excursions down to 400-500 RPM before going back to 700 RPM. Putting in new wires eliminated all of these symptoms.
my car is fine now, idles smoothly no misfiring.
but its just that i thinkkkkkkkk its my new tranny even though it ran fine before the cel i had no problem with first gear. i might have it checked out because its really bad.
but yea..... less then 250 miles a tank is pretty dam bad.
but its just that i thinkkkkkkkk its my new tranny even though it ran fine before the cel i had no problem with first gear. i might have it checked out because its really bad.
but yea..... less then 250 miles a tank is pretty dam bad.
You guys that say you can get only high 20s at best are wrong. I have never gotten less than 30mpg unless pulling a trailer. I have even gotten 37mpg on all interstate at 70mph or less just trying to see how good I could get. And yes I know how to calculate mpg. I even get gas at the same place every time to insure the pumps are shutting off around the same level every time.
to be getting those numbers u have to have some modifications to the exhaust,
ive gotten 34-35ish once with a Racing beat CB and CAI. That was summer all highway for 3 1/2 hours. I really don't remember the speed i was traveling at but I wanna say 65-70mph for an average.
drgnzadiel101
Member
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- 2002 mazda protege5
all stock i was getting 260 miles a tank. i got the axleback and k&n filter so ill post if there really is a difference
honestly thats a miracle, i havent heard anyone stock getting over 33-34 before. the highest i have ever heard for our cars modified was 41 but i forget who and what they had done. must of have tail winds that day ha
Just for the record, I got consistently less than 18mpg for the last 4 tanks. No CELs, car feels kind of underpowered but I can't compare since I only have if for 4 months. Didn't do any investigation/tuning/mechanic diags since it's too cold to DYI & it's kind of hard to go to a tech if there is no cel/other symptoms. It just sounds to me as a DYI diag task that will take forever.
I have an auto & my last tank lasted for 305 km (~14.5mpg). Something seriously wrong, I know. I'm just waiting for a damn CEL [can't believe I actually said that
]
I have an auto & my last tank lasted for 305 km (~14.5mpg). Something seriously wrong, I know. I'm just waiting for a damn CEL [can't believe I actually said that
]drgnzadiel101
Member
- :
- 2002 mazda protege5
Just for the record, I got consistently less than 18mpg for the last 4 tanks. No CELs, car feels kind of underpowered but I can't compare since I only have if for 4 months. Didn't do any investigation/tuning/mechanic diags since it's too cold to DYI & it's kind of hard to go to a tech if there is no cel/other symptoms. It just sounds to me as a DYI diag task that will take forever.
I have an auto & my last tank lasted for 305 km (~14.5mpg). Something seriously wrong, I know. I'm just waiting for a damn CEL [can't believe I actually said that
do a tune up and replace o2 sensors. you should be fine
kboutsider
Member
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- 2003 Protege 5
According to the app on my iPhone I'm getting around 25.5mpg.
i too am always above 30 unless i go "screaming" down the highway at like 85-90 (did that going to cleveland in december) and got 27mpgJust for the record, I got consistently less than 18mpg for the last 4 tanks. No CELs, car feels kind of underpowered but I can't compare since I only have if for 4 months. Didn't do any investigation/tuning/mechanic diags since it's too cold to DYI & it's kind of hard to go to a tech if there is no cel/other symptoms. It just sounds to me as a DYI diag task that will take forever.
I have an auto & my last tank lasted for 305 km (~14.5mpg). Something seriously wrong, I know. I'm just waiting for a damn CEL [can't believe I actually said that
finally someone knows the pain of this crappy gas mileage
Maybe you got the Protege "hybrid" (pow)
The rear O2 sensor was replaced by dealer 4mo ago. But I'm guessing the front O2 is the one used by the CPU for fuel trim, so I'll be looking at that too (someday). Other possible reasons for crappy gas might be:
- exhaust leak before or shortly after the O2 sensor - clean air might be sucked in the exhaust and the O2 sensor would detect an increase in O2 thus resulting in more fuel added to mixture. Prime candidate for me since they also replaced the exhaust.
- MAF/EGR dirty (long shot)
- clogged injectors, if they don't spray it right then it burns bad
- spark plugs for the same reason
I'm waiting for a USB ODBII diagnostic kit so I can read some of the parameters, maybe they will offer more hints. Will open a thread on that when I get to it. Till then I hope my cat doesn't burn down.
johnny mp5
Member
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- Mazda Protege5
im having the same problem.. getting around 250-270 a tank 
gotta get this pos to a mechanic
gotta get this pos to a mechanic
