Bad fuel mileage, no black smoke, no check engine light. ...

Q: Bad fuel mileage, no black smoke, no check engine light.

asked by on August 08, 2017

My car has an issue where I'm getting under 20 mpg, I have inspected the fpr, Maf, and the fuel injectors. Car also has sluggish acceleration, and the engine shudders under WOT below 3000 rpm. My car has 273,000 miles

My car has 273000 miles.
My car has a manual transmission.

Hi there. Most of the time, poor fuel mileage is due to dirty O2 sensors, EGR valve, mass air flow sensor or throttle body itself. If these components are dirty or damaged, it can also cause engine misfiring or rattling during acceleration as you’ve described. To identify the source issue, it might be a good idea to have a professional mechanic come to your location and complete a car is getting worse gas mileage inspection.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Car vibrates/shakes when sitting still in idle (in gear or in neutral).

This sounds as if you have a low idle condition. I can say your car isn't likely to suffer a catastrophic failure because of this. With a condition such as this, it is normal for it to run rougher when...

1999 mazda 626 has no fuel and no spark

It sounds like you may have an issue related to power getting to both the ignition system and the fuel system. I would suggest checking to make sure there is power running to the ignition module and the fuel pump...

Battery light was on and now car won't start and keys stuck in ignition

Hi there. It more than likely that you are experiencing an issue with the alternator or the main relay as opposed to the battery itself. Once your car starts, power to all components and accessories is provided by the alternator;...

Related articles

A Buyer’s Guide to the 2012 Hyundai Azera
The The Azera offers an overall good value for the class and price point. The sleek styling is hard to overlook – for a large sedan it’s about as eye-catching as they get. This Hyundai also boasts respectable power that’s...
The Best Used Cars to Buy If You Just Got Your License
If If you are a new driver, congratulations on getting your license. Now, you need to think about what type of vehicle to buy. Ideally, you’ll choose a used car that isn’t overly expensive, and is reliable and safe while...
Top 10 PZEV Cars for Eco-Friendly Drivers
Teddy Leung / Shutterstock.com The whole idea of a PZEV (that is, a partial zero-emissions vehicle), seems paradoxical. You’d think it’d have to either be zero-emissions or not in the category at all. But as contradictory as...