Engine knock when cold start

[G-143744]

Does anyone get engine knock when cold starting the 3.3 L TT?

 

[NS_Stinger]

Its totally normal and its the high pressure fuel pump. If you lightly blip the throttle at startup it will completely go away.

 

[D.J.]

Does anyone get engine knock when cold starting the 3.3 L TT?

Any engine knock is absolutely not normal.

Are you trying to describe a gentle tick? Like the ticking sound of the high pressure fuel pump?

Do you have the gentle tick sound as heard in this video?

 

[Buzzman12]

I have the cold start up ticking noise, which I also had in my 2017 Mazda 6. Same noises. I presume it's perfectly normal.
Runs nice and quiet after a bit of warmup.

 

[Thomby]

I have the cold start up ticking noise, which I also had in my 2017 Mazda 6. Same noises. I presume it's perfectly normal.

Your Mazda also had a direct injection engine. If you search high pressure fuel pump tick, you'll find YouTube videos of other cars making similar noise.

The reason it sounds like upper engine tick (like older engines with noisy lifters) is that a direct injection HPFP is basically an extra cam lobe and lifter, just actuating a pump instead of a valve.

And it's outside the head, so despite the heavy duty foam rubber cover, it's still pretty noisy.