Q: My car won't shift up right away when accelerating hard

asked by on January 28, 2018

My car won't gear up when hitting the highway. I accelerate but will stay around 40-50 mph. When this happens an intermediate check engine light appears. I can slow down and the car will jump into the next gear and the check engine light will turn off. I drive a 2004 Grand Prix.

My car has 123000 miles.
My car has an automatic transmission.

To determine the exact cause of this issue, I would recommend having your trouble codes scanned by a qualified professional. If the check engine light is on, a code will be stored in your vehicle that can give an indication what might be wrong with the transmission.

Hi DJ. Thanks for contacting us today. There are a few possible reasons why your car is having this issue. First, a faulty shift solenoid will cause this to happen, as will an obstruction of debris in the transmission hydraulic lines, an inner seal failure or a worn or faulty torque converter. The intermittent check engine light could mean that this issue is due to a faulty sensor or electrical component within the transmission. This is something that is best diagnosed by a transmission specialist, so you should probably contact a local transmission shop to see what they can do to help in this case.

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