Q: Engine won't rev past 2500 rpm?

asked by on October 10, 2016

I've checked for leaks, found none, cleaned & replaced MAS sensor, same problem. Replaced throttle body, no change. Replaced, throttle motor relay, no change. What is next?

My car has 175000 miles.
My car has an automatic transmission.

Engine hesitates during acceleration Inspection $79.99 - $89.99 Get a Quote

Hi, thanks for writing in. You may have been on the right track with the throttle body. I went down this road with an XK that was going into limp-home mode and not allowing the engine to rev up. In that case, the throttle body was the answer, but it didn’t solve the problem until I disconnected the battery for about thirty seconds, then hooked it back up. The car performs a kind of re-boot where the ECU and the throttle body have a little handshake (you can hear it when you turn on the switch making a little zip,zip sound) and the ECU learns the values of the new throttle body.

Disconnecting the battery is no small thing, you will also have to re-initialize a number of other features, radio code, window motors, possibly the door locks, but doing this re-boot may put you back in business.

Here at YourMechanic, we can have a technician come to your home or office to inspect and diagnose this issue for you, and make or suggest the necessary repairs.

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

What others are asking

Battery Light and Low Fuel Light on with no power

This is a common issue among this generation of the Chevy Trailblazer and is generally the result of one of two things. A weak battery can easily cause this to happen. There is also a known problem with the...

Car stalls, rpms go up, & no power

Hello. This can be caused by a number of things. I usually start by scanning the computer for codes. This will give me an indication of anything the computer is seeing. If it is not seeing anything, then it may...

Loud squealing - 2002 Chrysler Town & Country

Hi Vanessa. Any of the pulleys that the belt rides on could be faulty or there could be something leaking onto the belt causing it to make the noise and worsen. For an issue like this, a proper diagnosis of...

The car shut off at the traffic light, difficulty accelerating

Hello there, ESP will generally not cause the vehicle to die. It sounds like you have a few issues with the lack of power, starting, and the car dying. A few items can cause all three of these. Most common...

Possible electrical issue

This sounds as though you are having multiple problems that would need to be addressed. The broken latch may be the cause of the dead battery, but not the Check Engine Light illumination, or the radio not working; the radio...

Lights wont go off - 2002 Honda Civic

Hello. From what you describe, it would appear that your vehicle is experiencing some sort of electrical issues. If its the brake lights that are staying on then the first thing I would do is check the stoplight switch mounted...

Rattle when cold engine - 2006 Ford Mustang

Hello. This could be a variety of many things and may be difficult to pinpoint without physically inspecting the car. Many cars tend to have small or subtle vibrations and rattles as fasteners, nuts, and bolts become loose over time....

Will broken Axel Rings Cause check engine to go on?

I'm going to go out on a limb here and say it is very possible that the computer is performing a rationality test by comparing the inputs from VSS and ABS wheel speed sensors (WSS). When it doesn't see the...

How Does Engine Braking Work?

Engine braking is the process of using the engine to slow the vehicle down instead of using the vehicle brakes. Engine braking can be used on both gas or diesel engines and is used to slow a vehicle down or...

Related articles

How Do Rotor Engines Differ From Regular Engines?
Rotary engines use three-sided rotors inside an oblong housing instead of pistons. Rotary engines create lots of horsepower, but aren't as efficient.
How Air Filters Affect Horsepower
Air Air filters work to clean the air entering your engine’s combustion chamber. A good supply of air and oxygen is very essential so that the engine can burn fuel efficiently and give you the horsepower you need to drive....
How a Modern Engine Works
You You turn your key in the ignition, and the engine fires up. You press the gas and the car moves forward. You take the key out and the engine turns off. That’s how your engine works, right? It's a...