Horrible MPG, No Apparent Problems
- Thread starter 86.5
- Start date
tfhorst;1779521 said:
I'd have to assume you mean acceleration wise. I still managed to get 8.3 seconds 0-60, with a terrible clutch. I wanna say it was 9 something with the 4.30s, but back then I didn't know better and just dropped the clutch. If I drop the clutch with the 3.90s its about 9 seconds as well. I never slipped the clutch with the 4.30s however... Swapped the diffs before I knew better, lol.
God i need boost..
Hey all, I know it's been a while since I started this thread. But, I figured it was better than starting another. The car has since had a fuel system flush, replacement of the filter and pump, due to someone giving me a fresh can of DIESEL (in a red can) to fill the car up with. (I was worried about making it to the station from my driveway.) Boy, was that a fun day. Anyways, the car still gets around the same mileage. As far as I know the air filter is clean, there is no CEL's, I've kept up with oil changes, and there is no BHG. Very rarely, usually on a cold morning when it happens, or the second start of the day, the car will start, idle to 1k, drop to 500 or so, then shudder and die. If I give it slightest bit of gas and get it to idle for a few seconds, this goes away. Very strange. Other than that, this is the only thing the car has done. The plug wires aren't terribly old, if I remember right they were labeled 2008. Is this really down to short trips? If it is I guess that is unavoidable, because I live in an urban area where everything is close. It still has the stock muffler, do you think that replacing it with a Borla dual exit unit would help the mpg?
Thanks guys
Thanks guys
You never mentioned how you drive the car, meaning you have the accelerator pedal to the floor at every stop. You should have no problem getting-18 mpg with city driving only- driving like a normal human being.
How many fuel leaks are under the car?
How many fuel leaks are under the car?
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Backlash2032;1779258 said:
How do you check what gears you have? I have a 90s NA white package with TEMS I know it has LSD but no idea on gear ratio.
drogon;2008632 said:
If you still have the original diff that came with the car then your car will have 4.30's. All N/A's had 4.30's, the sport package just made it a LSD.
Last tank on my 7mgte I got 27.1. I was surprised it was that good for a 25 year old engine. That was on the freeway 2 hrs each way to a car show with the cruise set on 70. Stock except for Megan DP, catless, Blitz Nur Spec
drogon;2008654 said:
No problem!
grsupra87;2008675 said:
They do surprisingly well on the interstate. I went on a 8 hr round trip a few weeks ago and had 25.2 mpg in my 7mge cruising somewhere around 70 mph all the way. Pretty good for a 25 year old car like you mentioned, and one that runs almost 3500 rpm on the interstate due to the aforementioned 4.30 gears.
This makes me laugh. So one CEL light if fine but horrible MPG is not? not like a CEL light could ever effect MPG right?86.5;1778648 said:
atmperformance;2008681 said:
Especially not an exhaust manifold leak that is barely audible, yet trips the 25 because the fuel trim is now maxed out.
I got terrible mileage in my 90 GTE until I did the following: Replaced O2 sensor (*VERY* important), replaced stock intake with K&N filter, replaced stock exhaust with 3" hi-flow exhaust. These were all done in one swoop, but as a whole, my MPG's jumped.
Also, its not expensive to get your fuel injectors cleaned. I sent mine off and got a before and after report. None needed to be replaced, all suffered various degrees of clogging. If I had known how inexpensive this was, I would've done it long ago.
Note: K&Ns and other "oiled" air filters have fallen out of favor due to possible damage to AFMs. Perhaps a dry Apexi would be a better choice.
Also, its not expensive to get your fuel injectors cleaned. I sent mine off and got a before and after report. None needed to be replaced, all suffered various degrees of clogging. If I had known how inexpensive this was, I would've done it long ago.
Note: K&Ns and other "oiled" air filters have fallen out of favor due to possible damage to AFMs. Perhaps a dry Apexi would be a better choice.
ZoomZoomZoom;2009044 said:
An oiled air filter should not damage a vane-style AFM like the 7M engines have. The oil will contaminate a fine-wire AFM found on a lot of late model cars and skew the sensor readings. Unless you have some sort of conversion to a fine-wire AFM on your Supra. I agree with the O2 sensor 100%. My mileage was bad but not horrible and I failed the emissions testing due to elevated HCs. No CEL, but a new O2 sensor fixed things right up. Passed emissions and went from avg. 15 MPG to 18 MPG. The ODB-I system in these cars don't do a sensor back-check, and blindly accepts whatever the sensor tells it, even if it is way off.
BTW, Last year I got a chance to take my Supra on a road trip. 365 miles away. Averaged about 75 mph with the cruise on, (the long stretches with absolutely nothing I was cruising at 90!) and got about 27 mpg. These cars cruise great!
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^ In the interest of accuracy a couple of things. First, oiled gauze filters can contaminate the Karman sensor used in a GTE. Second, the statement regarding O2 sensor checking is incorrect. It it were true the entire reasoning behind OBD would be invalid.
http://www.autoshop101.com/forms/h34.pdf
Page 7 of 9 on the pdf to learn about the 7MGTE airflow meter.
Page 7 of 9 on the pdf to learn about the 7MGTE airflow meter.