15 mpg? What's going on?
Posted: Sun Sep 25, 2005 1:22 am
Any idea why I'd only be getting 15mpg? The last two tanks have gone like that. I know this car isnt that fuel efficient, but that seems kinda extreme.
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15 mpg? What's going on?
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Posted: Sun Sep 25, 2005 1:27 am
Leaking fuel? Bad Coil Pack? Yucky Spark Plugs? Bad Sensors? I'd check those things...
Posted: Sun Sep 25, 2005 1:44 am
How do I check the sensors?
Posted: Sun Sep 25, 2005 1:46 am
Check their voltages...read pinouts from the ECU..etc...Splinter wrote:How do I check the sensors?
You might want to try to clean the MAF. You might also want to try replacing the PCV valve..that can kill mileage too.
Posted: Sun Sep 25, 2005 2:21 am
Hey Splinter
That car always did about 26mpg hiway, I'd think it should be good for at least 20-21 around town if you're not spoolin the turbo all the time.
You dont have a check engine light do you? If you are running rich in feedback mode (after warm up, off boost) the O2 sensor should through a code.
Gary
That car always did about 26mpg hiway, I'd think it should be good for at least 20-21 around town if you're not spoolin the turbo all the time.
You dont have a check engine light do you? If you are running rich in feedback mode (after warm up, off boost) the O2 sensor should through a code.
Gary
Posted: Sun Sep 25, 2005 2:49 am
Nope, no check engine lightAll_talk wrote:Hey Splinter
That car always did about 26mpg hiway, I'd think it should be good for at least 20-21 around town if you're not spoolin the turbo all the time.
You dont have a check engine light do you? If you are running rich in feedback mode (after warm up, off boost) the O2 sensor should through a code.
Gary
Although it just occured to me that I've reset the ECU a couple of times (while working on the electrics Ive disconnected the negative terminal from the battery)
Could the mileage drop that badly while the ECU is relearning?
Posted: Sun Sep 25, 2005 4:05 am
Um.. where would I find the MAF sensor? 
Posted: Sun Sep 25, 2005 4:08 am
It's the gizmo bolted to the air filter housing with four 10mm-head bolts.
Posted: Sun Sep 25, 2005 4:10 am
cheersvrg3 wrote:It's the gizmo bolted to the air filter housing with four 10mm-head bolts.
Just use electrical contact cleaner on it?
Posted: Sun Sep 25, 2005 4:16 am
Contact cleaner might be good, but I've always used either isopropanol (swish it around in a ziploc bag of the stuf) or brake cleaner (spray it very gently).
Posted: Mon Sep 26, 2005 3:32 am
Anyone know the answer to this?Splinter wrote:Although it just occured to me that I've reset the ECU a couple of times (while working on the electrics Ive disconnected the negative terminal from the battery)
Could the mileage drop that badly while the ECU is relearning?
Posted: Mon Sep 26, 2005 4:02 am
Yes, mileage is usually a little low when it's learning. A couple hundred miles should be more than enough to relearn.
15 mpg still seems low though.
15 mpg still seems low though.
Posted: Mon Sep 26, 2005 4:04 am
I got 23 when relearning, and the second tank I got 27 
If it doesn't improve, then you can start panicking 
If it doesn't improve, then you can start panicking Posted: Thu Oct 13, 2005 4:45 am
Cleaning the MAF and replacing the PCV seems to have helped.
I'm about 1/3 of the way into the tank with 84 miles on the trip odo.
I'm about 1/3 of the way into the tank with 84 miles on the trip odo.