Terrible gas mileage, running rich?
12-13-07, 04:34 PM
#26
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12-13-07, 06:57 PM
#28
I replaced my stock pump with a Walbro a couple years ago and instantly got shitty mileage and less power in the bottom end. I went back to the stocker and all is good.
Regardless of what you do to improve your mileage, whether it be a ECT sensor or whatever, you should get a stock pump and put it in with a new sock filter. A walbro is enough pump for a modded TII but way too rich for an NA.
Pingpong, do you have a Walbro in your car or stocker?
Last edited by scrip7; 12-13-07 at 07:02 PM.
12-14-07, 03:14 AM
#29
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BINGO.
I replaced my stock pump with a Walbro a couple years ago and instantly got shitty mileage and less power in the bottom end. I went back to the stocker and all is good.
Regardless of what you do to improve your mileage, whether it be a ECT sensor or whatever, you should get a stock pump and put it in with a new sock filter. A walbro is enough pump for a modded TII but way too rich for an NA.
Pingpong, do you have a Walbro in your car or stocker?
I replaced my stock pump with a Walbro a couple years ago and instantly got shitty mileage and less power in the bottom end. I went back to the stocker and all is good.
Regardless of what you do to improve your mileage, whether it be a ECT sensor or whatever, you should get a stock pump and put it in with a new sock filter. A walbro is enough pump for a modded TII but way too rich for an NA.
Pingpong, do you have a Walbro in your car or stocker?
All this just makes me realize how much easier and cheaper it was to work on my bike. All I had to do on that was adjust the air/fuel mixture screw to lean it out......
12-14-07, 03:42 AM
#31
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Ironically, I was debating between getting either the RX7 or upgrading my bike to a Honda CBR600 F4i. Sometimes (read: every time I'm stuck in traffic or looking for a parking spot around campus or filling up on gas), I still wish I had gotten the bike.
12-14-07, 09:01 AM
#33
Engine, Not Motor
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Has the ECT been tested, or are you just going to replace it?
Also, while you are there have the mechanic replace the harness connector as well. 99% chance that the old one is about to fall off.
12-14-07, 05:11 PM
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im just gonna replace it. i think the previous owner drove the **** out of the car and didnt do any maintenance. i think this might also be related to my temperature gauge, usually on most cars the temp gauge is about half way on normal operating temperatures. well mine barley reads about 1/4.
12-15-07, 10:39 AM
#36
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im just gonna replace it. i think the previous owner drove the **** out of the car and didnt do any maintenance. i think this might also be related to my temperature gauge, usually on most cars the temp gauge is about half way on normal operating temperatures. well mine barley reads about 1/4.
12-15-07, 10:40 AM
#37
12-15-07, 03:47 PM
#38
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Do not replace the the coolant temp sensor without testing it first. IMO is unlikely this is the problem, so it could be a waste of money.
As Aaron said above, if the ECU thinks the engine is cold it will increase fuelling. But IMO it's very unlikely the sensor could fail in this manner. It's just a simple thermistor, so it can't fail in one "position", it either works or it doesn't. If it fails, the ECU ignores it and assumes the engine is warm (176degF). This makes the engine run poorly when cold, but it'll run normally when it warms up. This would actually decrease average fuel consumption slightly.
Always test sensors before replacing them. In this case a simply voltage reading at the ECU will prove whether the coolant temp sensor is okay.
As Aaron said above, if the ECU thinks the engine is cold it will increase fuelling. But IMO it's very unlikely the sensor could fail in this manner. It's just a simple thermistor, so it can't fail in one "position", it either works or it doesn't. If it fails, the ECU ignores it and assumes the engine is warm (176degF). This makes the engine run poorly when cold, but it'll run normally when it warms up. This would actually decrease average fuel consumption slightly.
Always test sensors before replacing them. In this case a simply voltage reading at the ECU will prove whether the coolant temp sensor is okay.
12-15-07, 04:01 PM
#39
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so yeah, my motor runs like crap when i start it up and its smells terrible, a real gasy smell, but when it warms up it runs like a champ and the gas smell goes away. when its warmed up it runs great and the gas smell goes away
12-15-07, 08:45 PM
#40
Eats, Sleeps, Dreams Rotary
My car's mileage seems to have gone down the crapper as of late.
I seem to get about half the mileage as usual.
I'm sure part of it has to do with jackrabbit driving style and lack of cruise control... but it smells like it's running way richer than usual.
It seemed to start from about the time my air conditioning hoses came undone... but I doubt that's related.
I don't think it's timing or TPS, since I set them...a lot. And my coolant temp and O2 sensor are about a year old.
I personally think either my ECU is retarded (which might also explain the ridiculously inconsistent idle), or I have a weak rear leading ignition coil (either that or it's timing is off, compared to the front rotor, which is probably an ECU issue).
I seem to get about half the mileage as usual.
I'm sure part of it has to do with jackrabbit driving style and lack of cruise control... but it smells like it's running way richer than usual.
It seemed to start from about the time my air conditioning hoses came undone... but I doubt that's related.
I don't think it's timing or TPS, since I set them...a lot. And my coolant temp and O2 sensor are about a year old.
I personally think either my ECU is retarded (which might also explain the ridiculously inconsistent idle), or I have a weak rear leading ignition coil (either that or it's timing is off, compared to the front rotor, which is probably an ECU issue).
12-15-07, 09:59 PM
#41
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u cant tell me that this is normal operating temperature....
right now my gas is just slightly under half and i drove for 45 miles, mostly city. running on premium gas. what can be wrong?
right now my gas is just slightly under half and i drove for 45 miles, mostly city. running on premium gas. what can be wrong?
12-16-07, 10:18 AM
#42
Engine, Not Motor
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That's quite low.
Has some idiot removed the thermostat from you car? If it has been removed, the car may never warm up and you might be in cold start constantly. If the thermostat is aftermarket, replace it with a Mazda unit.
Has some idiot removed the thermostat from you car? If it has been removed, the car may never warm up and you might be in cold start constantly. If the thermostat is aftermarket, replace it with a Mazda unit.
12-16-07, 05:51 PM
#43
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that cant be the case if my car floods and have hot start issues right?
12-17-07, 05:47 PM
#47
try not to boost. most ppl blame poor fuel economy on their car, when in most cases its the way they drive. this is especially true on turbo cars. look at you boost gauge(glance at the gauge, keep your eyes on the road) and try to drive without going over 0(kinda hard for the small turbo but doable). sure you'll be slower in traffic but you'll also save gas. and you'll be a better driver
12-17-07, 06:33 PM
#49
There were no survivors
I went from ~250 miles on a full tank to about ~340 miles (mixed driving) just by finally getting around to swapping out my 150k mile drive shaft with a brand new one 
Taken Saturday as I was filling up the tank: 351.4 miles
Taken Saturday as I was filling up the tank: 351.4 miles