Q: Performance issues when driving and idling, RPM dropping abruptly

asked by on October 19, 2016

My 2008 Ford Explorer Sport Trac has 103k miles and I'm having performance issues when I press gas it feels like I'm hauling a ton of gravel and almost have the gas to the floor and the RPM only reach about 2500-3000..on hills its much much worse..driving at 60 mph my RPMs are 15-1800 when normally around -2000..when I let off the gas the RPMs drop very fast down to almost 500.not a gradual drop..when ideling the rps are low and sounds like at any moment the motor will go dead..but never does..not less than a month ago my transmission was completely rebuilt.I have changed plugs and wires and replaced fuel filter..this helped at first..I guess my next step is the fuel pump witch is going to be a hassle..any ideas on what might be causing my problems before I start the process of replacing g the pump

My car has 103000 miles.
My car has an automatic transmission.

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Fuel gauge broke.
It sounds like you may have a bad sending unit in the fuel tank. Sometimes the old fuel sending unit floats no longer float in the fuel tank and will not show the proper level, these must be replaced (https://www.yourmechanic.com/services/fuel-gauge-sender-replacement)....
Noise while idling, difficulty shifting
Without hearing the noise myself, it will be hard to make an accurate assessment for your 2008 Chrysler Aspen. In many cases, where the noise source is not obvious, chassis ears may need to be used to locate the source...
Tire rubs against inner fender well.
The damage to the lower control arm bent that bad would cause tire to hit fender. You may have also damaged spindle, strut, tie rods. You will also need alignment after repairs are done to make sure it is in...
Engine surging on 2008 audi a4 Quattro
Hi There, What you are describing is a common problem with a dirty or faulty mass air flow sensor. The mass air flow sensor (https://www.yourmechanic.com/services/mass-airflow-sensor-replacement) monitors air intake as it is mixed with fuel prior to being injected into the...
Thermostat stuck
If you are referring to the engine cooling system thermostat, if that thermostat is stuck closed or partly closed, your engine will overheat but such will be obvious upon reading the engine temperature gauge on the instrument panel. Obviously, if...
Jumping dead car battery but alarms keeps beeping? 2002 Honda Accord
Hello - most modern cars "interpret" a battery swap as a possible theft attempt (i.e. hot wiring). To shut off the alarm each time a battery is replaced (or you jump it off from dead), shut the engine off in...
Car died while driving. I can start it but it will die after 2-3 seconds. 2004 Honda Civic.
If the car is starting but immediately stalling typical causes for such immediate stalling are a faulty mass airflow sensor, faulty engine coolant temperature switch/sensor (typically at cold start only), faulty camshaft or crankshaft position sensors, worn spark plugs, wires...

Related articles

A Buyer’s Guide to the 2012 Ford F-150
The The best-selling pickup truck in the US for over 30 years, the Ford F-150 has a lot to offer in reliability, durability, and the features that buyers want in a truck. The 2012 F-150 is not only a tough...
The Best Used Cars to Buy If You're Towing a Boat
If If you’re towing a boat, the vehicle that you buy is largely going to depend on the size and weight of your boat plus trailer. Most cars, realistically, aren’t cut out for the job. We recommend a pickup truck...
How to Get Ford Dealership Certified
Ford car dealerships offer automotive technician jobs to mechanics who are certified through either the ASSET or the FACT program.