Skip the auto shop - Our mechanics make house calls

Q: Bad instant acceleration on high speeds. Works just fine on low end speeds 0-60.

asked by on

On the highway when I'm going about 70 I give it gas but the Jeep doesn't react quickly. It will accelerate if you hold it down for a couple seconds but not as quick as it should. I noticed it sometimes doesn't even accelerate. I have to give it even more gas to see if something will happen. It jumps to about 3000-4000 RPM from 2000 and starts to accelerate faster as if it shifted to a lower gear. A couple months ago after a 3 hour long highway drive I got into the city roads with lights. After stopping on a light I remember the Jeep would not want to accelerate lightly. I'd have to give it more gas and it would jump in RPM as if it wasn't receiving enough fuel. My guess is the fuel pump or fuel filter but I wanted to ask a professional before acting. Thank You.

My car has 85000 miles.
My car has an automatic transmission.

Hi there. It is possible, the fuel pump and/or fuel filter is responsible for the lack of power at freeway speeds. It could also be, the exhaust system is restricted ie; restricted/plugged catalytic converter. The lack of acceleration at low speed and high speed may be a faulty MAP (manifold absolute pressure) sensor incorrectly calculating engine vacuum. There are more possibilities and proper diagnoses should be performed. Replacing components without diagnoses, can be expensive and time consuming without resolution. I recommend having your vehicle’s slow to accelerate at 70mph be diagnosed and repaired by a certified technician, such as one from YourMechanic.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  • Home
  • Questions
  • Bad instant acceleration on high speeds. Works just fine on low end speeds 0-60.

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

Q: ABS light is on

There could be several reasons as to why your ABS light is on in your Jeep Wrangler. One of the most common reasons is due to a faulty wheel speed sensor. Without additional information however, it may be time to...

Q: Oil light is on and my car won't turn over

The issue your having is going to depend on the details of what happened when it overheated. If you were running the vehicle without any coolant, the engine could have reached 280°. When a vehicle reaches this extreme or hotter,...

Q: Air conditioner making noise

You have an A/C leak. Dye needs to be added to the system, and the system needs to be recharged. Pressure gauges need to be attached to verify proper A/C system operation. You may also have a compressor issue that...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...