Knock sound when turning car off
Knock sound when turning car off
Occasionally, when I turn my car off, there's a knocking sound, fast at first and then 'winds down' until it goes away (probably 2-3 seconds). It sounds, and feels, like the engine is off.
I looked at this thread: https://www.crossfireforum.org/forum...ine-knock.html but didn't really find anything concrete.
Seems like it's only been doing it the past couple months, which I've replaced the ABS/ESP control modules, throttle body, and added a CAI. None of these seem like they would be the cause of the problem. I've changed the oil, using 0w-40 (8 quarts) and the correct WIX filter, but aside from that I have no idea what could be going on as I've not heard this in any of my other cars.
I'll try to get a sound file to post today or tomorrow, but until then, any ideas?
I looked at this thread: https://www.crossfireforum.org/forum...ine-knock.html but didn't really find anything concrete.
Seems like it's only been doing it the past couple months, which I've replaced the ABS/ESP control modules, throttle body, and added a CAI. None of these seem like they would be the cause of the problem. I've changed the oil, using 0w-40 (8 quarts) and the correct WIX filter, but aside from that I have no idea what could be going on as I've not heard this in any of my other cars.
I'll try to get a sound file to post today or tomorrow, but until then, any ideas?
Re: Knock sound when turning car off
Originally Posted by ProjectMayhem
And it probably is. I had to replace the upper coolant hose because the fan slowing rubbed a hole in the side and made the hose blow. Have someone turn the car on and off for you with you looking under the hood maybe?
Go to Chrysler.com > owners and enter your VIN to check if your car is part of the recall.
Last edited by 70GT6; 06-28-2010 at 07:14 PM.
Re: Knock sound when turning car off
Originally Posted by ProjectMayhem
And it probably is. I had to replace the upper coolant hose because the fan slowing rubbed a hole in the side and made the hose blow. Have someone turn the car on and off for you with you looking under the hood maybe?
I really can't see the fan hitting the hose when the engine has stopped because it would be too obvious and the hose would not last too long.
I would think that if some object was in the heating fan area it may hit the fan there and that has certainly occurred before.
Re: Knock sound when turning car off
Originally Posted by hines.eddie
do you have the six speed or the auto? because i have the same noise when turning the car off. i though it was the engine but when i push in the clutch and turn it off there is no knocking sound. maybe something in the transmission.
Re: Knock sound when turning car off
Originally Posted by Infinite
6spd. Both make the same noise. The litters are hydraulic when they lose pressure on shut down they chatter
all 6spds make this noise then? Thanks for the reply.
Re: Knock sound when turning car off
Guys, it's always a good practice to let your car idle for 1 minute before shutting it off in your driveway....especially a turbo charged car. it allows the engine to circulate & cool down an engine especially after it's been driven hard.
Also a slight knocking clinging sound is normal upon shutting. As it's the exhaust system contracting after it's expansion during the heat up with the engine heat. It's a normal sound. Other knocking is not normal. Try a higher gasoline octane to limit engine knock & run-on after shut down.
Hope i helped a bit!
Also a slight knocking clinging sound is normal upon shutting. As it's the exhaust system contracting after it's expansion during the heat up with the engine heat. It's a normal sound. Other knocking is not normal. Try a higher gasoline octane to limit engine knock & run-on after shut down.
Hope i helped a bit!
Re: Knock sound when turning car off
Holy smokes, forgot I even started this thread :|
It ended up being my cooling fan. Seems that it was slightly off-balance and rubbing around the outer rim of the fan.
Easiest way to find out if it's the fan is to have someone else turn your car off after the fan has been running.
It ended up being my cooling fan. Seems that it was slightly off-balance and rubbing around the outer rim of the fan.
Easiest way to find out if it's the fan is to have someone else turn your car off after the fan has been running.
Re: Knock sound when turning car off
Originally Posted by antonio311
Guys, it's always a good practice to let your car idle for 1 minute before shutting it off in your driveway....especially a turbo charged car. it allows the engine to circulate & cool down an engine especially after it's been driven hard.
Also a slight knocking clinging sound is normal upon shutting. As it's the exhaust system contracting after it's expansion during the heat up with the engine heat. It's a normal sound. Other knocking is not normal. Try a higher gasoline octane to limit engine knock & run-on after shut down.
Hope i helped a bit!
Also a slight knocking clinging sound is normal upon shutting. As it's the exhaust system contracting after it's expansion during the heat up with the engine heat. It's a normal sound. Other knocking is not normal. Try a higher gasoline octane to limit engine knock & run-on after shut down.
Hope i helped a bit!
Last edited by SillyMan; 07-21-2010 at 01:28 AM.
Re: Knock sound when turning car off
coolant doesnt make a knocking sound, nor does the throttle body.
The M112 motors have hydraulic lifters... When they lose oil pressure on shutdown they collapse, causing valvetrain chatter for the last few revolutions of the motor as it spins down. Thats what you are hearing. If it were the fan it would be a constant sound as the fan would be hitting that same point everytime it engaged.........................
The M112 motors have hydraulic lifters... When they lose oil pressure on shutdown they collapse, causing valvetrain chatter for the last few revolutions of the motor as it spins down. Thats what you are hearing. If it were the fan it would be a constant sound as the fan would be hitting that same point everytime it engaged.........................