SIGNIFICANT MPG DECLINE HAS OCCURRED IN THE LAST...

2007 Jeep Grand Cherokee

Tiny

diane j

November, 27, 2012 AT 3:33 AM

Significant mpg decline has occurred in the last month, I have done a tunes up, check brakes, air pressure. Is there any thing else that would cause a decline mpg? It appears to continue to decline.

5 Answers

Tiny

racefan966

November, 27, 2012 AT 3:36 AM

Is the engine light on? You say you did a tune up what did you replace? I wouldn't hurt to get a can of seafoam and put it in the gas tank next time you fuel up.

Tiny

diane j

November, 27, 2012 AT 11:01 AM

Engine light is not on. I have tried seafoam. Tune up included spark plug changed and belts.

Tiny

racefan966

November, 27, 2012 AT 3:52 PM

When you replaced the plugs what did they look like ie- black, white or? Have you replaced any other parts? Which engine is in it? How is the power?

Tiny

diane j

November, 28, 2012 AT 3:34 AM

Dont know the color but I have not replaced anything recently. Power is okay. The rpms are normal. V6 engine. I did have the trans module replace in January

Tiny

racefan966

November, 29, 2012 AT 3:37 PM

I do believe that this Jeep has a mass air flow unit. What I would like you to do is buy a can off mass air flow cleaner and then remove the mass air flow and spray out the inside of it (cleaning it) and put it back and let me know how that does. If the sensor wire inside it dirty or? Then that can reduce the mpg and sometimes alot.

Please login or register to post a reply.

Engine Oil Change and Filter Replacement
Engine Oil Change and Filter Mercedes Benz
Engine Oil Change and Filter Honda CR-V
Engine Oil Change and Filter Ford Super Duty
Engine Oil Change and Filter GMC Sierra
Engine Oil Change and Filter BMW 5 Series
Engine Oil Change and Filter Chevrolet Camaro