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hi there guys, i'm relatively new to the sub and it's my first time posting for some help regarding my car.
I currently drive a 2012 lexus is250 that's coming up on 149k miles. everything's been great so far, but as of late, there's a noise coming from the engine bay that happens on a cold start after I haven't driven the car in a few days. the noise, which sounds like a metallic ticking/rattle, goes away after the engine is warmed up (approx 10-15 minutes) and if I recall correctly it doesn't seem to get louder or quieter whenever I drive it. I know that these motors are notorious for the loud noise of the injectors as the motor is running but i'm certain it's not that. it also does not seem to affect driveability and from what I can tell the car functions even when the noise is still present and after it goes away.
based on searches from the forums, others have mentioned that it could be one of the vvti cam gears causing the noise.
I have also spoken to a local mechanic who believes that because the car wasn't driven in a few days, it goes into a state of low oil pressure, which causes the lifters inside the motor to create the noise. the mechanic mentioned that I should switch to a heavier oil, such as 5w30, which should make the noise go away.
please let me know what your thoughts are and I look forward to reading all of your responses. if there's any other additional info that I need to provide, please let me know and ill be glad to do so.
If you have no check engine light for anything specific, it may as well just be a warn out pulley or the belt.
Have you tried spraying the belt, or some of the pulleys with a bit of water while the engine is still cold to see if the noice goes away? -an easy trick to check if it's just that.
Also, when was the last time you serviced/replaced the water pump? -could be it as well, since we know the blades in the water pump are metallic, and if they are warn, you could have a noice coming from there as well.
What I can recommend is start with the basics, try and locate exactly from where the sound is coming from, before replacing anything, get a big flathead screwdriver, and use it as a tool to listen for knocks on the engine, for example, put the flathead on one of the injectors, and you ear on the handle, check the next, then the next, and so on, you will figure it out.
Good luck.
hi there guys, i'm relatively new to the sub and it's my first time posting for some help regarding my car.
I currently drive a 2012 lexus is250 that's coming up on 149k miles. everything's been great so far, but as of late, there's a noise coming from the engine bay that happens on a cold start after I haven't driven the car in a few days. the noise, which sounds like a metallic ticking/rattle, goes away after the engine is warmed up (approx 10-15 minutes) and if I recall correctly it doesn't seem to get louder or quieter whenever I drive it. I know that these motors are notorious for the loud noise of the injectors as the motor is running but i'm certain it's not that. it also does not seem to affect driveability and from what I can tell the car functions even when the noise is still present and after it goes away.
based on searches from the forums, others have mentioned that it could be one of the vvti cam gears causing the noise.
I have also spoken to a local mechanic who believes that because the car wasn't driven in a few days, it goes into a state of low oil pressure, which causes the lifters inside the motor to create the noise. the mechanic mentioned that I should switch to a heavier oil, such as 5w30, which should make the noise go away.
please let me know what your thoughts are and I look forward to reading all of your responses. if there's any other additional info that I need to provide, please let me know and ill be glad to do so.
thanks a lot!
I'll start with I may catch some flack for this but I routinely use STP oil treatment in my engines as it is fortified with Zinc and moly. Yes, newer engine designs have minimized the need for these products by getting rid of flat tappet cams that have high wiping / high shear loads on the oil that break it down. An added benefit of the product is it sticks around when a hot engine is turned off and let to sit for weeks.
OP, buy the best oil you can afford add STP oil treatment to it.
Report back.
That said you might look up if your vehicle had the recall campaign done for the cam gears. I think it was fixed by 2012.
Recently heard similar sound herd in video posted by adngo 18 (IS 350 / 87,500 miles). Upon startup (vehicle sat overnight), ticking is not heard however, after approximately 4:20 minutes, it can be heard from passenger side rear where Bank 1 spark plug 5 is located (refenced in photo by Yellow arrow). No codes or Check Engine light present. Apologies, unable upload the video;
Recently heard similar sound herd in video posted by adngo 18 (IS 350 / 87,500 miles). Upon startup (vehicle sat overnight), ticking is not heard however, after approximately 4:20 minutes, it can be heard from passenger side rear where Bank 1 spark plug 5 is located (refenced in photo by Yellow arrow). No codes or Check Engine light present. Apologies, unable upload the video;
Normal. You're hearing the HPFP for the direct injectors kick on after a few minutes from a cold start (it's located directly where your arrow was pointing).
Unrelated, looks like you have some coolant sprayed around the engine bay. Check your reservoir/water pump for leaks (assuming this is your photo of course)
Normal. You're hearing the HPFP for the direct injectors kick on after a few minutes from a cold start (it's located directly where your arrow was pointing).
Unrelated, looks like you have some coolant sprayed around the engine bay. Check your reservoir/water pump for leaks (assuming this is your photo of course)
Thank you for the follow up Zmon, and providing that the ticking heard after first starting vehicle, is normal operation of the High Pressure Fuel Pump. I appreciate it. Thought the fuel pump was located in the fuel tank. Is there a high pressure fuel pump dedicated to the direct injection located in are referenced by the arrow? After vehicle reaches normal operating temperature, does the ticking subside? Also, appreciate you pointing out the presence of coolant on engine cover. Photo is a "stock photo".
Thank you for the follow up Zmon, and providing that the ticking heard after first starting vehicle, is normal operation of the High Pressure Fuel Pump. I appreciate it. Thought the fuel pump was located in the fuel tank. Is there a high pressure fuel pump dedicated to the direct injection located in are referenced by the arrow? After vehicle reaches normal operating temperature, does the ticking subside? Also, appreciate you pointing out the presence of coolant on engine cover. Photo is a "stock photo".
The HPFP is driven by the camshaft near cylinder #5.
The GS has a cover to drop a few dB off the thump sound it makes. The DI FI's will always be ticking and loud.
The HPFP is driven by the camshaft near cylinder #5.
The GS has a cover to drop a few dB off the thump sound it makes. The DI FI's will always be ticking and loud.
Thanks 2013FSport. That's different from the VVT-i cam gear, correct?
Yes, just another lobe on the camshaft. The cams turn at 1/2 crank speed and with a single large lobe driving the pump it has a nice thump to it.
Understood, and thank you for following up and explaining that the HPFP is cam driven and separate from the VVT-i (Variable Valve Timing with intelligence), which is also cam driving.
I'm now at ease knowing it's a normal sound and why it's produced. The Port injection system is used upon startup, and the separate high pressure Direct injection system used during full load operation.
07-28-21, 07:40 PM
Mysterious ticking noise from the engine bay
