I have a 1996 Nissan Maxima and I have always got about 30 miles per gallon or more, but for some reason, here recently, my FE dropped for no obvious reason, and I am trying harder than ever! I replaced my O2's, I have checked my air filter (it is in brand new condition), I have changed my oil regularly (with synthetic), I have pumped my tires to 45 psi, and much more.
For some reason, now, I can not even get 20 mpg, but I used to always get at least 30
Nothing seems to fix this! Does anybody have any clue what could cause a sudden drop in FE this intense?
Ah, a new muffler, huh? I did not think about that, as a matter of fact, my muffler has got quite loud lately, also, it is the original, never been replaced before, and has holes in it, so this just might be worth looking into. I still don't understand how that alone could cause a change this HUGE! I am getting about 15 mpg, but I used to get about 32! I am even trying harder now than I used to!
Do a compression check...Check Cat to see if plugged...Have you lost power?
2006 Jeep Liberty CRD...Founder of L.O.S.T.
OME 2.25" Lift w/ Toyo Open Country HTs 235/75/16s
ASFIR Alum Eng/Tranny/Transfercase/Fuel Skids
2002 Air Box Mod...Air Tabs (5) on Roof...(3)each behind rear windows
Partial Grill Block with Custom Air Scoop and 3" Open Catback Exhaust
Lambretta UNO150cc 4 Stroke Scooter
Well, yes, it does seem it has less power than it used to. When I first got it, you could easily spin the tires without even trying, but now, it seems that even at WOT from a complete stop, it will not spin. As far as the cat, I have been getting trouble codes on that for months now, but I have no funding for this, and my father refuses to pay for a new one when he can always reset the codes before inspection, however, if I had any income, I would definately do this.
Well, the muffler is definitely breathing just fine, it has got excessively loud, and because of my worn out rear suspension (rear sits excessively low) and the fact that (for some stupid reason) I tend to go "All-terrain" in it as if it were a jeep or something, there are many exhaust leaks in the muffler AND pre-muffler because they have both scraped a lot of rough surfaces (there are holes in both the muffler and pre-muffler).
off road cars? That brings back memories( kiss destroyer eight track days).
You may just be letting the car run more to keep warm since it's colder now.
New plugs usually give better mileage and don't cost much ( can always just clean and check gap).There are many ways to lose MPG; same amount to get it back.