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No Acceleration 6th Gear, low Acceleration on 5th

Hi,

This is my first post so I hope I’m in the right place, I am currently the owner of a 2015 Chevrolet Trax, it has 31000 KMs and I have bought it used so I don’t have any warranty and am bringing it to a mechanic tomorrow but would like some input so I can at least be a bit more informed.

My current problem is that when I try to accelerate to a higher speed, as soon as I hit 80kph (about 50mph) the car struggles to accelerate, it will drop to a high rpm then settle at 2000 rpm once I reach 100kph (about 60mph). I had a friend take a drive with me and we tried the Manual gear shifting mode (just a button for shifting up or down gears) and up to 4th Gear it was fine, as soon as I tried shifting into 5th it struggled to accelerate at all even with my foot all the way down, and on 6th gear it even started to decelerate with my foot down. With my foot down in 5th the engine didn’t sound like it was reving very high and in 6th they didn’t climb at all (I think it stayed around 1500 rpm) He thinks it’s the overdrive or the turbo, is he accurate with his guess or does anyone else have any other thoughts? For notes the car does not have trouble starting, does not stall while driving or any other issues I can think of but I’m open to checking if you have suggestions.

Thanks for taking the time to read and if you have any answers or suggestions!

You either have a problem with engine power or a weird transmission issue. By weird, I mean a failed one-way clutch in the stator of the torque converter. I say “weird” because it’s very rare. Have a good mechanic see if there is an issue with the engine.

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Thanks for the input!

any check engine lights illuminated? It may be worth going to a shop and see if any transmission codes are stored, too.

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Sorry I did forget to mention that the engine light did come on, not right away but about halfway through my commute.

and what is the code behind the CEL? it should be in a P1234 format. Share it here so we can see if it is related.

A 1.4L turbocharged engine doesn’t have much oomph if the turbo malfunctions. Sounds like that might be your problem.

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Hey everyone, I took it to a mechanic and he said the code was for a Turbo Under Boost/Pressure (cant remember) and after he cleared the code the car was fine, they think some moisture tripped a sensor which put the car into Limp mode and which is why I had acceleration issues. He test drove it with me with his diagnostic tool and nothing came up and it drove normally, didn’t charge me and just said if it happened again bring it in and they’d do a closer inspection of the turbo. Thanks everyone for all the help and ideas!

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