Causes of Knocking Sound in Engine While Idling

The causes of why an engine makes a knock noise when it is idling.
Mechanical Knock or Detonation Knock
Mechanical Knock: A mechanical component is broken.
Rod Knock (Lower half of engine speeds up with engine RPM. Rod knocks are usually a "thud" dull sound.)
Valves (Top of engine more clacking sound than knocking.)
Lifter Tap Knocks (Top of engine Lifters are usually high pitched and a "clean" tap sound.
Possible Causes
Dirty or Low Oil
Bad oil pump
Wear and tear
Detonation Knock: Something causing the cylinder to fire early.
Engine Timing Off
Bad or slipped timing belt or chain
Bad Cam or Crank Position sensor
Bad Knock Sensor
Carbon Deposits
Engine often continues to run when shut off.
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[@michaeldenlinger5573]

There’s a knocking sound in my van that I mostly hear behind my pedals. I don’t hear it when I open the hood nor when I crawl under the van. No check engine light either

[@rojoperro310]

Caravan?

[@victoriagirdler4795]

Could be a bad blend door actuator if you only hear it inside the cabin.

[@atomicdmt8763]

I wonder why specifically at (more at) IDLE? Ill check my engine mounts... and consider timing chain also. I have a slight (lifter tick) gettting better w additives/cleaning... but at idle I continue to get an irregular knocking sound. thanks!

[@Ricky07070909]

I think I have a valve knock after the timing belt change (Which they had to do twice because the timing was off the first time ) What's your thought?

[@jonathanSmith-rc3vk]

1997 ford f150 with 4.6 with headers. after my truck warms up at idle it has a slight knocking noise in bottom of engine. Thought it was transmission so i rebuilt and that wasnt it, When i give it gas or drive it doesnt knock, only at idle. What could be doing this, It has no check engine lights and truck runs great other than that knock.

[@yungsauceee]

2012 Veloster noise around cylinder 3 on the top super low when warm but once I hit the gas the tapping starts compression tested just above 170 is that because I have carbon buildup?? 2012 Veloster 150k 1.6L no turbo only check engine codes for catalyst bank 1 and evap emissions no flow

[@trevorstieger6762]

I have a stuck egr valve and I heard it can cause a knocking sound. Is this true and how if so...

[@brooklyn7941]

What if u hear like a tap noise when ur in drive or in reverse but it goes away when ur in park? It doesn't increase when I drive /accelerate neither it's like sounding somewhere in the drivetrain area

[@kcroc44]

I’m experiencing the same exact thing in my 05 Yukon xl

[@Luzurus]

I appreciate this video a lot. I am currently facing issues with my 2005 Honda Civic that will knock with acceleration but as soon as I let off the gas the knocking noise goes away. Any thoughts on what might be causing this? I will hear the noise as car cold stars but it seems after it warms up, the noise is not present as long as my foot is not on the gas pedal.

[@tangedal9983]

Did you figure it out?

[@maxximum18]

Good vid !! got a knocking sound and a flashing check engine light and when i checked the code it was po107 and thoughts?

[@hakenkreuz7076]

2018 jl Wrangler 3.6... Upon startup has loud knocking until the rpm's go down , after warm its quiet.

[@geofferymaxmax]

I have a 2004 ford explorer 4.6 bought on the cheap about 2 years ago it had a bad trans replaced it and runs great. But ever since I bought it it's had this noise at first I thought it was the timing chain and tensioners. I replaced the timing and tensioners noise still there. Then, I replaced the oil pump and while the noise is still there I did notice that it wasn't as bad as it used to be I'm thinking because the oil pump is the High volume one. But the noise is still there it's more noticeable on the passenger side. I have gotten under it and put a brick on the gas to see if the noise would go away but to my surprise, it's still there. I also remember when I bought it the first thing I did was change the oil and about 2-3 quarts of oil came out of the engine. what do you think brother? I would really appreciate a response ive been dealing with this on and off since I bought it. thanks for your video and I wish you lots of blessings.

[@HVAC_Mechanic]

It is hard to say, but since the transmission was just changed, I would check the torque converter bolts. Sometimes things don't align correctly and can cause a knocking noise.

[@geofferymaxmax]

@@HVAC_Mechanic uuhh great feedback I’ll check them and let you know. Thanks for the reply.

[@andrewmarsman3294]

Maybe could also be you need to run on midgrade gas instead of 87 octane?

[@jpp3389]

My son has a 2007 scion tc..when he starts it up there is a very loud knocking sound when idling.we got it towed home next day checked the fluids and saw that there was absolutely no oil very low so we added oil checked and it was level but when we went to go start it up again the very loud knocking sound was still there..we are unsure where to do at this moment..we know mechanic shops is very pricey..

[@karliec702]

Same issue here! 07 Scion tC

[@joshitheyoshi2533]

I have a ticking noise at idle on my 2001 BMW 325i. I'm going to get the engine oil and filter changed in a few days. Hopefully that will fix it. Does anyone else have any other info?

[@tommytsadventures]

My son was driving the other night while it was pouring down rain and went through a water puddle and stalled the car. Water got sucked in through his air intake. He didn't try to start it and instead had it towed to my house. I removed the coil packs/plugs and turned to car over to spray water out of the cylinders. We did this several times throughout the day until no more water was spraying out. We dried everything off and replaced the plugs. I checked the oil and it doesn't appear to have any water in it although we are going to replace it anyways. The car started right up but now has a knocking noise (I didn't run it long). Could this be because there is still water in the cylinders or something worse, like a bent rod? I was going to pour a little bit of marvel mystery oil into each cylinder but wasn't sure if I should.

[@ericknoxkwarteng1833]

Is there no code on it? I had a knocking noise and tried many things which didn't work out. later a mech discovered fuel pressure sensor was having internal short and had blown the fuel regulator fuse causing high fuel pressure in the system creating that knocking noise.

[@tommytsadventures]

@@ericknoxkwarteng1833 there was no codes. I'll have to keep that in mind.

[@83144600]

Here one for you then. Help needed please. I have a VDJ78R Diesel Toyota Landcruiser and it has an Intermittent ticking sound lower left rear of the Block. This can only be heard at operating temp once thermostat opens. I have good oil pressure no metal in oil it done 194,000kms. The only component in that area is the scavenge oil pump. Can these make a ticking sound before they start to fail? Thanks for anyone's help/input Appreciated!

[@HVAC_Mechanic]

Here is a link to a forum for Landcruiser's with this problem. They can likely help more than me. www.landcruiserclub.net/community/threads/the-dreaded-ticking-noise.149559/

[@j.c.2787]

What about a single tick... No ticking just one tick as soon as i turn it over?

[@raquelguzman6195]

Hello my wife 2013 Lexus GS 350 is making this knocking noise and a code 1604 pop out

[@brandonorozco8358]

My car only knots when accelerating past 4000 RPM. when I'm idle. Or moving very slowly there's no sound only when the rpms are high

[@jovo21]

Man rn ive got a knock in my engine bay and idk where from exactly. The wngine seems to be running fine and everything but theres the knocking noise and its loudest at lower rpm. It only gets worse as the engine gets warmer.

[@motabaiofficial7776]

What kind of car

[@Ngcron215]

Bro my 2010 ford Taurus does it to and I took it to a car shop and they told me they don’t know it might be the pistons but they are not sure bro I drive and I don’t hear it when I stop I hear it but like you said when it warm up it’s sooo lound but car still runs like a beast

[@motabaiofficial7776]

@@Ngcron215 they have variable valve timing problems. Common problem in ford vehicles. They can develop engine problems because there is no proper shifting due to the timing issues

[@ericknoxkwarteng1833]

my engine makes a loud knock noise at start up and disappears after about 30mins, there is P008 code on it. what do I have to check?

[@HVAC_Mechanic]

A P0008 code is usually a timing belt or timing chain.

[@afiqariff10]

@@HVAC_Mechanic after adjust the timing back to normal. will it fix the noise?

[@StaticShuttle]

My 1gfe knocks on start up but doesn’t when reving

[@Williams.Watches]

Mines doing the same did you find out what is was?