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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #1
I definitely will take it to my guy soon to get his opinion but for now I was wondering if anyone know what a light ticking noise from the top of my engine it only happens when it’s cold and it stops after it warms up it’s not loud or anything but it’s almost like someone tapping really fast on my engine with a pen or something
 

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2014 ATS 3.6 Premium RWD, 2016 Corvette Z06, 2018 GMC Sierra Denali 2500HD Diesel
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How new is this car to you? The direct injection system is a bit more audible in cold weather, it is the sound of the cam driven high pressure fuel pump and you can definitely hear it ticking if you listen for it. If you hear the direct injection "tick" along with another tick, then something else is going on but if you are only getting one tick it is likely just the high pressure fuel pump. The noise is semi-localized near that location but the sound propagates through the high pressure rail that feeds the individual injectors so it isn't a single point sound source.

GM put a lot of sound deadening around the engines when they first introduced direct injection around 2008 because of the tick but because most gas power cars now use direct injection engines with the high pressure common rail systems it isn't as big of a concern. So modern engines get less sound deadening, my 2008 CTS had baffled covers to contain the sound which my ATS does not. Go to a Cadillac dealer and listen to a cold start of another 2.0T to see if the sound is similar.

Rodger
 

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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #3
How new is this car to you? The direct injection system is a bit more audible in cold weather, it is the sound of the cam driven high pressure fuel pump and you can definitely hear it ticking if you listen for it. If you hear the direct injection "tick" along with another tick, then something else is going on but if you are only getting one tick it is likely just the high pressure fuel pump. The noise is semi-localized near that location but the sound propagates through the high pressure rail that feeds the individual injectors so it isn't a single point sound source.

GM put a lot of sound deadening around the engines when they first introduced direct injection around 2008 because of the tick but because most gas power cars now use direct injection engines with the high pressure common rail systems it isn't as big of a concern. So modern engines get less sound deadening, my 2008 CTS had baffled covers to contain the sound which my ATS does not. Go to a Cadillac dealer and listen to a cold start of another 2.0T to see if the sound is similar.

Rodger
How new is this car to you? The direct injection system is a bit more audible in cold weather, it is the sound of the cam driven high pressure fuel pump and you can definitely hear it ticking if you listen for it. If you hear the direct injection "tick" along with another tick, then something else is going on but if you are only getting one tick it is likely just the high pressure fuel pump. The noise is semi-localized near that location but the sound propagates through the high pressure rail that feeds the individual injectors so it isn't a single point sound source.

GM put a lot of sound deadening around the engines when they first introduced direct injection around 2008 because of the tick but because most gas power cars now use direct injection engines with the high pressure common rail systems it isn't as big of a concern. So modern engines get less sound deadening, my 2008 CTS had baffled covers to contain the sound which my ATS does not. Go to a Cadillac dealer and listen to a cold start of another 2.0T to see if the sound is similar.

Rodger
im doing my cams and valve springs sometime in the spring/early summer so I’ll probably just have him check it out then to see if I need to replace it or something
 

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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #4
How new is this car to you? The direct injection system is a bit more audible in cold weather, it is the sound of the cam driven high pressure fuel pump and you can definitely hear it ticking if you listen for it. If you hear the direct injection "tick" along with another tick, then something else is going on but if you are only getting one tick it is likely just the high pressure fuel pump. The noise is semi-localized near that location but the sound propagates through the high pressure rail that feeds the individual injectors so it isn't a single point sound source.

GM put a lot of sound deadening around the engines when they first introduced direct injection around 2008 because of the tick but because most gas power cars now use direct injection engines with the high pressure common rail systems it isn't as big of a concern. So modern engines get less sound deadening, my 2008 CTS had baffled covers to contain the sound which my ATS does not. Go to a Cadillac dealer and listen to a cold start of another 2.0T to see if the sound is similar.

Rodger
sorry didn’t mean to do that twice 😂 but it’s been turning perfectly fine no problems and no power loss it has 52,000 miles and I’m excited for what’s next
 

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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #5
sorry didn’t mean to do that twice 😂 but it’s been turning perfectly fine no problems and no power loss it has 52,000 miles and I’m excited for what’s next
Driving**
 

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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #6
It also only happens on idle too
 

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1992 DeVille, 2013 ATS 3.6
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Well if it is only on cold start it could just be the valve train for a bit before it gets warmed up. I always fire up my cars and let them idle down and then some before ever putting them in gear and pulling away. I follow Jay Leno’s advice (re-classic Ferraris) which is to let the needle come just off of “c” before moving and never beat on the thing until it’s fully warmed up.

My LFX makes injector noise during normal operation. Not a problem.

it used to ping under Load and I ended up having to replace a coilpack that went bad. Def not the best sound and probably did some lite damage.

on myfirst motor she tickedalmost always and would ping when I jumped on it in first gear. Motor blew within 20 k miles.

I am 30k miles into my second long block and she purrs. Only clicking is injectors.
 

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I have a neighbor who has a Mercedes c class and fires it up and immediately throws it in drive and takes off. The valve train rattle coming from that poor ice cold thing makes me sad to hear. I’d just let it sit for a min before going but that’s just me I guess.

as soon as you light the engine off the whole top end is soaked in oil as the squirters do their job as soon as the motor starts turning so you can take offright away but I always let the carcalm down before pulling away. It’s like jumping out of bed too fast in the morning. Might throw the ol back out if u move too fast =)
 

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2016 ATS Premium 6-spd MT
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I have a neighbor who has a Mercedes c class and fires it up and immediately throws it in drive and takes off. The valve train rattle coming from that poor ice cold thing makes me sad to hear. ...
"The Best or Nothing." Just keep saying it.
 

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2014 ATS 3.6 Premium RWD, 2016 Corvette Z06, 2018 GMC Sierra Denali 2500HD Diesel
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The DI ticking from the injection system in my Z06 LT4 V8 is significantly louder when cold, the noise from the 3.6 in my ATS is slightly louder when cold. I suspect this difference across engines is related to clearances and the changing density of components between cold and warm leading to better sound conduction with a cold engine. I haven't looked at the tables but your 2.0T engine may call for slightly greater than normal rail pressure when at cold idle to provide for higher injection pressure and the richer mixture needed to quickly raise the front cats to operating temperature. Even modern synthetic oil is still slightly thicker at very cold starts and is better at conducting sound so it plays a role.

As long as you don't have two different rhythmic ticking noises, your engine sounds normal. All of the gas DI engines have this noise from the cam driven high pressure pump and the difference between engines depends upon layout, level of noise shielding, and to a small extent individual build variance.

A couple of other typical reasons for non-fuel system cold start ticking are the belt tensioner and in rare cases spark discharge from a damaged module or connecting wire. If it is due to spark, the problem should be noticeably worse in damp weather but this was typically a problem seen in older cars that don't use coil on plug style ignition systems and had long wires from the distributor to the various cylinders.

As to cold start, as soon as the engine stabilizes it is time to start driving it with a moderately light load on it avoiding heavy throttle or high RPM operation. Warmup via idling is one of the most destructive things you can do to an engine, cold operation doesn't make the engine happy and increasing the length of time in cold warmup is bad. Cold idling washes down cylinder walls and contaminates the crankcase due to incomplete combustion and you also have moisture in addition to fuel dilution during extended cold idling. Oil warms more slowly than coolant so avoid heavy load/high RPM until the coolant has come up to operating temperature for a few minutes and this is particularly true for engines which don't have an oil to coolant heat exchanger which also serves as an oil warmer instead of cooler during initial warmup.

Rodger
 

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As to cold start, as soon as the engine stabilizes it is time to start driving it with a moderately light load on it avoiding heavy throttle or high RPM operation. Warmup via idling is one of the most destructive things you can do to an engine, cold operation doesn't make the engine happy and increasing the length of time in cold warmup is bad. Cold idling washes down cylinder walls and contaminates the crankcase due to incomplete combustion and you also have moisture in addition to fuel dilution during extended cold idling. Oil warms more slowly than coolant so avoid heavy load/high RPM until the coolant has come up to operating temperature for a few minutes
This is good advice, as you always hear about the perils of cold engine driving, but also letting an engine idle for too long. It wasn't just Jay Leno as mentioned by someone else, but I also remember reading an interview with a Honda engineer that said, by far, the most important thing you could do to ensure longevity was to allow an engine to reach full operating temperature before using it hard. But, as people have pointed out, so many people just get in the car, twist the key and mash the gas. It's painful. Imagine people that live at the bottom of steep hills that have to rev their cold engines every time they leave home.

Any thoughts on gently revving an engine to warm it up a little? I noticed this is standard operating procedure in grand prix race garages (motorcycles and cars). Of course they can't simply drive around slowly to warm things up, but they don't seem to like simple idling either, so they tend to do repeated short, and not overly high rpm, revs (or throttle blips).
 

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Rather than revving the engine, put it in drive while holding the brakes to put some load on it. You can SLIGHTLY increase the idle speed (hold it under 1,000 RPM) for a minute or two which helps to heat the engine under some load and also creates heat in the torque converter which will transfer to the cooling system. Additional engine loading will occur via turning on headlights, seat heaters, and rear window defroster. This doesn't add much load but the alternator will be commanded to higher output which does increase engine load. But there is no need to overthink it and just try to get moving as soon as possible. On long trips, if the engine is really cold before starting in the morning from a hotel just off the interstate I will run around town for a couple of minutes to heat things a little before coming up to speed rapidly for an interstate merge.

GM has a great automatic warmup system for their 6.6L pickup truck diesel. When the ambient temperature is around 36 or lower within a few seconds after start (if the transmission is left in park) the Allison transmission is commanded into gear but with the output shaft still locked and the engine begins increasing from 600 RPM curb idle up to 1,200 RPM in small steps over a few minutes. During this time the variable exhaust vanes in the turbo are also set to full restriction as they are during exhaust braking to further heat up the engine. It is a very smooth operation that works beautifully to let the engine heat up under a reasonable load.

The only downside to the diesel warmup strategy was it scared my daughter when she was really young. I had strapped her into the child seat in the back of my 2006 and then realized after I started the pickup that I had left some paperwork in my home office and while I ran to pick that up the pickup went into its cold start strategy. It sounds exactly like a little jet engine with the turbo whining as it spools up with increasing engine speed and Anna thought she and the truck were about to take off without me on board.

Rodger
 

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I concur with what Rsing said. A friend of mine who was a Toyota master tech for 10 years taught me how when diagnosing or working on a car or issue that needed to be at operating temp, it was part of the procedure to raise rpm to 1,200 or so in order to bring the vehicle to operating temp so he could work on it.

he told me how he would do this as prescribed by Toyota as to not have to wait around forever or drive the car to be able to work on it. I found it interesting to learn that rpm sustained like that was prescribed to quickly warm. Loved talking to him for hours about automotive things
 

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On long trips, if the engine is really cold before starting in the morning from a hotel just off the interstate I will run around town for a couple of minutes to heat things a little before coming up to speed rapidly for an interstate merge.
Thanks for the feedback. I'm the same way about getting on the highway. I just recently moved to a location close to a couple of highways, and now that it's gotten cold I'm often faced with getting on while the engine is still warming up. I try to avoid it, but I'm unfortunately running late half the time. That said, I always try to baby it. Along the same lines, my cousin used to live at the bottom of a big hill. I hated leaving his house late at night because I didn't want to sit there idling for a while, and there wasn't any place to drive really except up the hill. The strain on the cold engine was painful.
 

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2019 CT6 Sport 3.0TT,2015 Luxury ATS , 2016 ELR, and Volt
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I have a neighbor who has a Mercedes c class and fires it up and immediately throws it in drive and takes off. The valve train rattle coming from that poor ice cold thing makes me sad to hear. I’d just let it sit for a min before going but that’s just me I guess.
Mercedes engines are extremely noisy especially when cold. When I bought my SL I had to compare it to several others before I accepted it. My neighbor's GL sounds like a diesel. It's hard to believe they get away with it.
 

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Mercedes engines are extremely noisy especially when cold. When I bought my SL I had to compare it to several others before I accepted it. My neighbor's GL sounds like a diesel. It's hard to believe they get away with it.
Of all the overrated brands, Mercedes has to be near the very top. Never been overly impressed by them.
 

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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #18
The DI ticking from the injection system in my Z06 LT4 V8 is significantly louder when cold, the noise from the 3.6 in my ATS is slightly louder when cold. I suspect this difference across engines is related to clearances and the changing density of components between cold and warm leading to better sound conduction with a cold engine. I haven't looked at the tables but your 2.0T engine may call for slightly greater than normal rail pressure when at cold idle to provide for higher injection pressure and the richer mixture needed to quickly raise the front cats to operating temperature. Even modern synthetic oil is still slightly thicker at very cold starts and is better at conducting sound so it plays a role.

As long as you don't have two different rhythmic ticking noises, your engine sounds normal. All of the gas DI engines have this noise from the cam driven high pressure pump and the difference between engines depends upon layout, level of noise shielding, and to a small extent individual build variance.

A couple of other typical reasons for non-fuel system cold start ticking are the belt tensioner and in rare cases spark discharge from a damaged module or connecting wire. If it is due to spark, the problem should be noticeably worse in damp weather but this was typically a problem seen in older cars that don't use coil on plug style ignition systems and had long wires from the distributor to the various cylinders.

As to cold start, as soon as the engine stabilizes it is time to start driving it with a moderately light load on it avoiding heavy throttle or high RPM operation. Warmup via idling is one of the most destructive things you can do to an engine, cold operation doesn't make the engine happy and increasing the length of time in cold warmup is bad. Cold idling washes down cylinder walls and contaminates the crankcase due to incomplete combustion and you also have moisture in addition to fuel dilution during extended cold idling. Oil warms more slowly than coolant so avoid heavy load/high RPM until the coolant has come up to operating temperature for a few minutes and this is particularly true for engines which don't have an oil to coolant heat exchanger which also serves as an oil warmer instead of cooler during initial warmup.

Rodger
Ok thanks man I’ve only noticed one ticking noise and i watched a video of what injector tick sounds like on bad and good ones and mine sounds exactly like a sound of a cleaner injector tick but yea I always let my engine calm down bc I have an upgraded exhaust and it always takes a bit longer to go to normal but when it’s just starting up the engine doesn’t seem to use its full power until it warms up and it also shifts really weird when that happens too but I think it’s just the cold
 

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2015 ATS4 2.0t fullly upgraded turbo system except for turbo and full custom exhaust 317whp 405tq
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Discussion Starter #19
I barley ever push my engine hard and as a huge plus I have a dual catch can system from mishimoto and keep up on all the maintenance just replaced the spark plugs and turbo also upgraded my ignition coils so I know I won’t be having any misfires
 
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