Q: Judder/lag when accelerating

asked by on September 26, 2016

Doesn't happen all the time but most times when I accelerate there's a judder/lag almost like a loss in power then suddenly picks up, feels Like it's jumpy, any ideas what this could be?

My car has 79000 miles.
My car has a manual transmission.

This could potentially be due to a faulty mass air flow sensor. This is a component that regulates the air coming into the intake system as it is mixed with the fuel prior to being injected into the motor. When this is not functioning properly, this will cause an imbalance in the fuel trim which will constantly be trying to recalculate. This will cause an intermittent lag as you describe.

This could also be due to a faulty throttle position sensor. I would recommend having an expert from YourMechanic come to your home to diagnose the hesitating acceleration using a scan tool which will indicate any potential fault codes that may be registered in your car’s computer as a result of this.

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