was getting 40 mpg...now suddenly only get 25

[khartley]

Yeah, I was getting 40-45 mpg highway, and then instantly it went down to 25. Anyone that has any ideas let me know. It's for my 95 GS.

Thanks.

 

[khartley]

Well I'm guessing it probably is my cat, my CEL light has been flashing on and off for quite some time now, and it does feel a little doggy at times. I don't have a data logger for this car, maybe I should get one, huh? I'll try turning power on to see if fuel is leaking from somewhere, but in the meantime I'll probably try and find a place where I can gut my cat and see what happens there.

 

[khartley]

Ok, here's an update. I gutted my cat, and it did NOTHING. Still getting shitty gas mileage. I did the fuel line leak test the guy above was talking about, and there was no fuel leaking, even after several minutes. I removed and cleaned my air filter and I checked my spark plugs which are all ok.

So, any new suggestions? My CEL light is blinking on and off more frequently now, I'm wondering if maybe a different sensor is going out? MAF sensor or something?

Any more ideas would be great, because I'm out of them.

 

[xveganxcowboyx]

Have you checked your codes? Just use an analog multi-meter on the diagnostic connector. It's probably explained in VFAQ.

 

[khartley]

Have you checked your codes? Just use an analog multi-meter on the diagnostic connector. It's probably explained in VFAQ.

I don't have the stuff to check codes myself on that car, and isn't it $100 or so to have a dealership do it? Maybe I should just pay it though, then I'd actually know what it is instead of guessing.

 

[Pure92TSi]

Advance auto or auto zone will do it for free.

 

[xveganxcowboyx]

Or you could spend $15-$20 on an analog volt-meter as suggested. You really should own one anyway... Or spend $40 on a datalogger and check codes with that.

 

[2-0turbo]

I think we need a tech article on how to compute fuel mileage. 40MPG is hard to believe for this car, GS or not. That means you were regularly getting 500-600 miles on a tank of gas? I don't think so. Seems everyone these days wants to brag about their fuel mileage. I heard some guy the other day brag about his Windstar minivan with 3.0 liter V6 gets "almost 40 MPG on the highway"--sorry, I don't think so. You need to fill-up at the same place and fill it up until it runs out of the neck to be consistent. The auto cut-off feature of every gas pump will be different. Parking on a slightly different slope will allow your tank to be "full" with different capacities.

Sorry for your loss (in mileage), but I think you are more accurately computing mileage these days. 25 is a bit low, but I would be happy if you get low to mid 30's out of this engine.

 

[redeclipse7782]

Clogged fuel injector('s)??? Did you say the cell was FLASHING or just coming on then shutting off minutes later? Try the STP fuel injector cleaner. I know if the cell is FLASHING then that means you are misfiring which usually means a bad injector or injector harness.

 

[khartley]

Advance auto or auto zone will do it for free.

I've been to all those places, and they all tell me that they can't do it for anything older than a 96.

 

[khartley]

I think we need a tech article on how to compute fuel mileage. 40MPG is hard to believe for this car, GS or not. That means you were regularly getting 500-600 miles on a tank of gas? I don't think so. Seems everyone these days wants to brag about their fuel mileage. I heard some guy the other day brag about his Windstar minivan with 3.0 liter V6 gets "almost 40 MPG on the highway"--sorry, I don't think so. You need to fill-up at the same place and fill it up until it runs out of the neck to be consistent. The auto cut-off feature of every gas pump will be different. Parking on a slightly different slope will allow your tank to be "full" with different capacities.

Sorry for your loss (in mileage), but I think you are more accurately computing mileage these days. 25 is a bit low, but I would be happy if you get low to mid 30's out of this engine.

And I'm sorry that you don't believe me, but I know how to use a calculator. I don't understand how it was doing that either, maybe it was running really lean. Maybe it was the fact that I never really take this car over 3 grand. Maybe the fact that I have no power steering or a/c. But I was getting 40mpg, because I did check it out. Back in the day I had a 94 GS, and when I checked that one, it was almost always at exactly 33 for on the highway. My old 94 GS was getting in town what my 95 is getting on the highway right now, or pretty close to that.
I appreciate your feedback, but please don't act like I'm a newbie - especially when it comes to something as simple as computing gas mileage.

 

[mitsuclipsegsx]

I've been to all those places, and they all tell me that they can't do it for anything older than a 96.

do it the old fashion way,i forget exaclty,but its something like turn the key on and off and the cel blinks and u count it like 1,2,3and check the code,i dont remember exaclty but thats what the guys at autozone did for my 95 rs it was the map sensor,good luck

 

[khartley]

Clogged fuel injector('s)??? Did you say the cell was FLASHING or just coming on then shutting off minutes later? Try the STP fuel injector cleaner. I know if the cell is FLASHING then that means you are misfiring which usually means a bad injector or injector harness.

No it isn't flashing, but it'll just come on and stay on for a few hours, or a few days, then go off for a little while again. Or anytime I unhook my battery, it is always off for quite a while. But if you still think it might be injectors let me know.

 

[khartley]

do it the old fashion way,i forget exaclty,but its something like turn the key on and off and the cel blinks and u count it like 1,2,3and check the code,i dont remember exaclty but thats what the guys at autozone did for my 95 rs it was the map sensor,good luck

Sweet, thanks. So are you saying that you were having the same problem as I am, and it was your map sensor? If anyone else knows more about this, I'm really interested in how to check that out.

 

[mitsuclipsegsx]

Sweet, thanks. So are you saying that you were having the same problem as I am, and it was your map sensor? If anyone else knows more about this, I'm really interested in how to check that out.

well i dont get bad millege well maybe i do 22 but thats city and i beat the piss outta her j/k , i had cel, autozone told me what it was,i cleaned my enigne hasnt been on since

 

[xveganxcowboyx]

Checking your codes is simple. Get an analog volt meter and set it for 10-12 volts. Pull the harness from the fuse areas of the driver seat. Turn on the key. Touch the probes to the outputs that are kiddy-corner from each other (there is only 1 set like this). Make sure the readout is going forward (polarities are not backwards). The needle will bounce forward and back or make long sweeps and will cycle through any and all codes repeatedly.

Example:
Sweep Bounce Bounce Bounce Pause Sweep Sweep Bounce.
Or a more visual method:
___ _ _ _ ____ ____ _

It will repeat this so you'll have to pick out the pattern. This particular example reads codes 13 and 21. A sweep equals 10 and will always come before and bounces. A bounce equals 1.

Any questions, PM me.