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Clicking Sound After Battery Reset, Initial Turbo Issue - Sonata Turbo 2.0

Hi all, I need some help with my 2011 Sonata Limited Turbo 2.0. I disconnected my battery yesterday to do some wiring-related work. After reconnecting my battery I have a clicking sound coming from the engine bay when the car is set to “On” and the engine is not running. I can’t tell if it is also clicking when the engine is on. After starting the car after that first battery reconnection, the car seemed to drive fine except for one major exception - it didn’t build boost at all; I would floor the pedal and the car just crawled and there were no turbo sounds to speak of. It was as if the turbo was electronically disabled or something of that sort.

Note, before I first disconnected the battery I had pulled some fuses to try and isolate the area I was doing wiring work, but I just ended up disconnecting the battery altogether. I double-checked that the few fuses I had pulled out were replaced properly.

I unhooked/reset the battery again overnight. As of this morning, the car now drives OK and builds boost and feels normal, however, the clicking sound is still coming from the engine bay with the car set to “On” and the engine off. I’ve done a little bit of reading but I’m a little bit out of my league here to know what’s going on. I’ve attached a photo of the area the sound seems to be coming from.

Maybe the sound is normal and I just never noticed before? It just seems odd with the turbo issue also happening. Any ideas and help is greatly appreciated. Thanks.

You more than likely are hearing your throttle trying to find home and or adjust itself. After a battery disconnect you should perform a Throttle relearn procedure. Look it up on the internet… most vehicles need to perform a relearn, some can do it on their own… some cannot. Look into this before moving on.

That looks like boost control solenoid. It may have got stuck open when you disconnected the battery. The engine wouldn’t build boost with it open.

Drive the vehicle for a while and see if the clicking stops.

When disconnecting a battery, computers/modules may have to go thru a relearn for things to return to normal.

And other times, a factory level scanner is required to reprogram computers/modules.


Sometimes we get similar posts about dash gauges, hvac doors doing something like this after disconnecting the car’s battery. Many of the actuators these days are controlled by the computer issuing a “move forward” or “move backward” command. But for the computer to know the actual orientation of the actuator it first has to find the “home” position. for example an actuator might be at any angle from 0 to 180 degrees after the battery is disconnected. Before the disconnect the computer knew it was at 45 degrees, b/c it kept track of every time it moved it forward and backward from its home position (0 degrees). The clicking sound you may be hearing is the computer trying to find the actuator’s home position.