High Fuel Consumption

[ffp1967]

Hi everyone,
I have a 2001 Dodge Caravan SE. I have been measuring fuel consumption for a while and don't get more then 15 miles per Gallon (mix of highway and city driving). This seems to be extremely low. The fuel system has been cleaned a year ago without making any difference. Does anyone have the same problem? What could be the cause of this pathetic gas mileage?

Thanks for your help!

[RIP]

I'll take it for granted you are a sensable driver who has taken steps to insure your driving habits are not the cause.

I get around 17/18 around town and 21/23 on the highway with my 96 3.8ltr. but, I live in a desert region where it's fairly flat. If it's hilly where you live in Illinois then you will get less. Comparing mileage across the country is comparing apples and oranges. There's too many variables.

If you truely have a problem, brakes and engine management would be the most likely areas to look at. How often have you had to change brake pads? If you're driving 15K miles/year you shouldn't have to change them more than every 2/3 years at most. If it's more often, you're either driving agressively or there may be a problem with the brakes. Slider pins, piston, or a master cylinder may not be allowing the brakes to release completely, making the brakes drag ever so slightly.

The engine management system uses numerous sensors to manage timing, spark advance, and fuel air mixture. A Service Engine Light (SEL) will light up on the dash indicating a serious malfunction is detected. The Powertrain Control Module (PCM) stores the error codes. These codes can be read by cycling the ignition key or using a scanner. That said, a sensor can give erronious data without generating an error code. It can fail to a point below the threshhold the PCM is looking for to generate the SEL. An engine analyser can detect this but, few shops are competently trained on how to use them. If I had to pick a most likely sensor for your issue I'd pick an O2 sensor. Others to consider are the crank and camshaft sensors, MAP sensor, throttle position sensor, engine coolant temp sensor, and the PCM itself.

You can spend big bucks chasing this issue. You have to determine if it's worth it to save a few bucks at the pump. First, make sure you're doing the basics like keeping the tire pressure up, driving sensably, completing scheduled maintenance, etc.