Hey guys I have a 95 850 turbo and I am getting really bad gas mileage the computer on the dash shows 14.6mpg city and 17.2mpg hwy on 4 gallons I get like 60 miles. Today my car was running and I unplugged the MAF sensor and the car still ran the same the idle didn't even drop but as soon as I put the car in drive that's when it stalls. Does this mean the MAF is bad?? since it still runs when it's unplugged?

 

If the MAF is bad it's sure to trip the check engine light.

Is your check engine light on ??

 

No the check engine light did not come on. So that's why it's weird because it should have came on

 

If you're not showing a check engine light I wouldn't think of replacing the MAF unless you test it with a meter and it checks out bad.

Have you done the basics and checked to see if you have a gas leak anywhere between the tank and the injectors? Clean air filter? Is the temp gauge reaching the 3'O clock position in the first couple minutes and holding pretty steady there? Tested the coolant to see if it's hitting 185+ degrees in case the sender is starting to go and running the engine rich because it thinks it's colder than it is.

Any chance you feel the transmission might be slipping, higher than normal RPMs for a given speed? Fluid level checked? Tire pressure?

Someone might have some other ideas but then you might get to the point of jacking it up and checking each wheel to see if they spin normally or if you find you have a caliper or parking brake shoe dragging.

Depending on your location it's that time of year when you lose some mileage due to the cold ( I'm in Minnesota) and also due to them running up to 10% alcohol in the mix in winter. But your numbers say something is eating your gas that shouldn't be.

 

Are you sure you're CEL is even there? PO may have removed the bulb to cover up an issue; not uncommon. Does it come on during bulb test?

 

The check engine light is there because when you just turn the ignition ON it lights up. I checked for visual gas leaks and could not see any, but my temp gauge is not at 3 o'clock I would say 90% of the time it's only about a 1/4 of the way up and only get's to 3o'cklock in heavy stop and go traffic. The coolant is full and everything else seems fine. I did notice that it needs the pcv system replaced, could that cause it??

 

A clogged or restricted PCV will make a mess pushing oil out past the seals but it shouldn't impact gas mileage.

You should check the actual, physical temperature of the coolant. If you're not getting at least 180 degrees at idle I'd recommend a new thermostat. If the thermostat is opening too early and you're not getting up to the proper temp the engine will be injecting more gas than it needs and will not set any code because it would see the condition as normal.

 

Sounds like you need a thermostat!