2010 Chevy HHR ticking noise from engine

I purchased a 2010 Chevy HHR 4-cylinder with automatic transmission & 50K miles last December. I am hearing a lite ticking noise when I gently press the gas pedal and the car begins to accelerate. To me it sounds like a lifter or sticking valve. I took it to a Chevy dealer & they acknowledged hearing the ticking noise but after two days they could not find the problem…no computer codes. Nothing! This is a weird problem since if you have the car in neutral, engine running, with the hood open…you don’t hear the noise. If I roll down the window when the car is underway I don’t hear the noise. If the windows are closed the noise is very apparent when the car is in gear and I accelerate lightly. As the RPM’s increase the noise seems to go away but you hear it again as the transmission shifts to the next gear and the engine is under load.

The car seems to run fine, the idle is not rough, the acceleration is spot on, gas mileage seems great. The oil is clean & changed at 47K.

Anyway…the dealer told me it could be an injector or something else but had no answers. A friend told me to try another oil change and use a synthetic oil. Someone else told me to put more insulation under my hood so I don’t hear the engine. I’m really frustrated with this noise and want to make sure I don’t have a serious engine problem. Can you help me understand what the cause of this noise might be?

2101 Chevy HHR? I’m good but a car from the future? I’m not that good. Seriously…you need to take the car to a good, independent mechanic and let them isolate the problem for you. Noise problems are nearly impossible to isolate unless you have access to the vehicle.

WAG if you hear no sound with the windows open, only when closed and accelerating I am thinking hvac problem, try some different settings and see if there is any change.

Try a tank of premium gas. If the noise goes away, it’s porbably a bit of engine knock.

I spoke to a fellow HHR owner who told me he “goes through fuel injectors like crazy”. He seemed to think it was a problem with the bigger 2.2L engine.

2101 Chevy HHR? I'm good but a car from the future? I'm not that good.

Clearly the warp drive’s dilithium matrix has broken down. OP needs to regenerate the crystals by bouncing a graviton particle beam off the main deflector dish. Duh.

OP my first step would be to put 1/3 of a can of Sea Foam in a full gas tank. This will do two things: If there’s crap accumulated on the valves, it will help it burn off. Gunk on valves can cause them to stick, so if your suspicion is right this has a good chance of fixing it. It will also generate smoke which will let you verify that you don’t have a bad exhaust header gasket, which can cause a noticeable ticking noise itself.

Noises can be subjective so it can be difficult to make a guess on things like this.
A ticking sound normally points to a problem in the valve train so a theory or two might be:
The car has low miles for the age so what about the possibility of a sludged valve lifter or valve timing mechanism due to the oil change regimen not being as strict as it should have been by the prior owner?

If this ticking is actually a spark knock or pinging there exists the possibility of a faulty knock sensor or more likely; an EGR system fault. Low miles, short hop driving, etc can contribute to EGR passages clogged up and which in turn can cause a spark knock.

A more ominous problem regarding the first paragraph could be if the oil pressure is affected by lack of oil changes and which in turn affects the timing chain tensioner.

I agree that you could try a tank of premium fuel as sort of a test for a potential spark knock situation. That’s easily done without much expense and no dirty hands.
You could also add a can of something like SeaFoam or Berryman B-12 to the engine oil and if the problem is related to a gummy lash adjuster those products could possibly clear it up.
Hope that helps.

One guess about the ticking noise- This comment from a Fuel systems/Noise & Vibration engineer- who owns a 2007 HHR - with 2.2l Ecotec engine I may have the same/similar ticking noise - it is called “Fuel hammer” noise. The fuel Injector pulses pulsate through the Fuel Rail assembly & makes the noise. It is present in many Fuel injected engines- This noise is generally suppressed and/ or insulated via many techniques- so even though present in luxury cars etc- you don’t have the pleasure of actually hearing it.
This does Not retract from engine performance, in any way- When my HHR was new, I wanted everything perfect- but really, if you have good experience with the car ( I have 175K miles w/o hardly any issues)- just Don’t worry about this! Good luck!

Thanks everyone for your input and comments. I will try your suggestions and hopefully rectify / isolate the problem. And…sorry about the title of this blog (2101 Chevy HHR)…my typing fingers got ahead of my brain:)

If you add Sea Foam to the oil, it’s usually recommended that you add it to the oil, and then drive it no more than 10 or so miles to the shop and get an oil change. Let it clean, but then get it out so that the oil can do it’s job lubricating.