Thread: MPG gone down the crapper

Nope I've been granny driving it since this started to see if that was the problem.

I've searched and I can't find the damn thing where is it located?anybody got a pic?

Same here, i noticed i used to have half a tank for 180 miles out of it, but now i get 140-150 or so. Don't hot rod the car and had the fuel filter and pump replaced a year ago too.

Facing from the front of the car, it's at the very left corner of the rear of the valve cover. Could be the problem, but I wouldn't have too much hope.

10-15% mileage drop in the winter is typical. But 20% like you're seeing is pretty extreme.

Maybe check for leaking injectors too. Especially with the cold i could easily see seals leaking. The seals (as well as the injectors, mostly) on my '91 were shot.

well the pcv valve can be stuck open and it will draw in unmetered air and that will allow your air fuel ratios to be way off esp if you are running maf when the maf is metering the air and you have more air coming in

Damn I need to pump gas every 200 miles!

Tire pressure, alignment? You running the heater? Are you carrying things around in your trunk that you never did before? It might not be one thing, but a sum of a bunch of little things.

How cold does it get in your area?

How as your MPG around this time last year?

Do you preheat your car before driving or do you drive it cold till it gets warm?

What kind of driving do you do? City, highway, mixed?

When was the last time you replaced the O2 sensor? Replace with a new Bosch one.

Idle at 900 RPM? Isn't that a little high? When the car is worm, my car idles at about 750-800

My MPG right now is about 22MPG mixed driving. But my knock sensor code is showing, so I will be replacing the knock sensor and will see if that helps.

I was able to get a universal Bosch O2 sensor for my car for $30 shipped on eBay. Check my post out on how to install it etc.

Now I also ordered a new Knock Sensor, Genuine OEM Nissan one for $60 shipped at eBay.



Interesting, I'll have to find that valve and try shacking it

Try a compression test and also check for gas in your oil. If you have fuel in your oil, you have bad rings somewhere.