Just started doing this. When driving, just before shifting the rattle noise is there and quits after the shift. Also, if I give it more gas or let off the gas then the rattle stops. But yes it is the hub bearings, I took the wheel off on the passenger side, and put it third and let it coast. No noise problems at high speed. I have a 2004 Honda Pilot that makes a rattling/ticking noise that corresponds when the RPMs reach above 3k, while accelerating. When clearances get excessive on the crankshaft journals the oil runs out quickly after the unit is shut off. It only occurs when I let off the gas, while the car is moving at any speed, and becomes very noticeable when I downshift. After I put everything back together it was fine for about a month then it started making a rattling/vibrating noise when accelerating. Transmission feels solid and smooth. I have noticed that when I come off the throttle or stay on a tiny amount of throttle there is quite a stange noise coming from the engine. Its strange because after i let the car sit over night if it rattles it starts up like normal and if it doesn't rattle it seems like there is a hesitation in starting, but it starts every time and the noise only last 10-15 seconds. (guessing its a little rich) Being on the rich side, when you let off the gas there is unburnt fuel making it into the hot exhaust at which point it "pops". A service of GSW Strategy Group, LLC. It only happens when pressing the gas and then only up until about 5 to ten mph, then it goes away. When those bolts are loose and you either let off the throttle or give it gas that forward and reverse jerk can cause the rattling noise. The grandmother didn't want to go to Florida. as your slowly releasing the accelerator listen for a faint rattling noise. There are no warning lights. Steering wheel doesn't affect it. Not so much of a rattle though. We compare design, practicality, price, features, engine, transmission, fuel consumption, driving, safety & ownership of both models and give you our expert verdict. Its only happen in 1st gear. I can not comment on the LWFW because my RS is totally stock. ok, so my car is making some funky noise. There is an abnormal engine "rattle" noise when decelerating (letting off throttle) between 1000 and 2000 rpms. The sound seems to come from the centre of the vehicle (middle seat in second row). Nope, it is in 2wd high. First time poster here. If I power back on the gas, it stops. Its not my tires because the sound stops when I stop coasting. Knocking / Rattle when entering and exiting V4 mode. First, you have to turn off all the hysterical lies of a media that have sunk beneath bias into pathology. The rattling sound goes away when the clutch is pressed in and comes back as soon as the clutch is released can do that multiple times until the engine drops down the normal idle speed. I am going to put the truck up on ramps and inspect the path back. Anyone else have this? Know what could be causing it?. & it happens when I lift completely off the gas peddle straight up. I was going to get new struts, but the Van needs a few other repairs done too, so trying to spread the money further. known issue: cats rattling When the engine is warm, I get a rotational rattling sound after I let off the gas and the revs are around 1500-2000. Noise sounds similar as if exhaust pipe falling off in front dragging into the pavement. Skip navigation 06 chevy colorado ratcheting noise when letting off the gas bob komani. Let off the pedal, be sure that whirling sort of rattling sound is gone and know that a new throwout bearing is in your immediate future. Just before/as the car was about to shift, traffic slowed down and I let off the gas suddenly. When you turn the car off it is very noticeable as the engine shuts down. sometimes its lound other times i dont hear it. hey everyone. Metal-to-metal noises — At times, a heat pump can make banging or clanging sounds like metal hitting against metal. wanted to get some opinions before bringing to dealership. It sounds as if you are describing pinging from too much load in to high gears. I have changed the air filter now and it is still making the noise. A service of GSW Strategy Group, LLC. When I let off the throttle above 50 mph to coast or slow down, sounds like a bearing noise, groaning grinding. I know this is probably totally unrelated, but my wife's Murano was doing the same exact thing. I think at some point I'm going to go with a Tial wastegate, but right now that's not the problem. It's not really a grinding noise, or a clunking noise. also i changed my oil about a week and a half ago or so and my truck was running fine no problem at all but now my oil gauge is reading low and when i come to a near or complete stop. Worn or otherwise compromised drive belts are a common cause of noises when accelerating. 0T 32K on the newly installed used (2010 engine). It sounds like a Harley… or a bad muffler, but the sound is clearly coming from the front of the car. There are no warning lights. I went downstairs and took a look at the furnice. Worn or otherwise compromised drive belts are a common cause of noises when accelerating. you can make out the drone on its way up, if that makes any sense. This noise is more noticeable on acceleration because the engine is working harder, making the noise louder. I have a v6 b5. When these go bad then will setup a rattle at idle and low rpms that is close to an injector rattle in sound. I knew 10,000 mile oil changes were too good to be true. Weird grinding/rattling noise during 1st gear Hey, just thought I'd ask about this in case anyone had the same problem. With an exhaust leak, the muffling of the noise is cut short, making the noise louder. The gas engine (ICE) has to be running. Car has 62k miles on it. Re: Whining noise when let off gas at 40-45 mph (lolobug22) Post by circuitsmith » Mon Dec 19, 2011 2:25 pm Change the trans oil and hope for the best. If your motorbike is out of gas it will crank the engine, but it will not turn over. When I speed up a bit and then let off the gas it clanks even more loudly and the frequency slows down. Obviously it has something to do with the engine being under load, because when I rev up to 2000 rpm while parked, there is no rattling. Well the rattle is still happening. Brakes, Steering, Suspension, Tires, & Wheels - Vibration,Rattle. Hubs are brand new timkens. The timing chain tensioners on the 06 and 07 Sonata 3. after letting foot off gas pedal (Deceleration) - Help This has been an ongoing problem. Lastly, drive 65 in 4×4 mode…give it gas then let off the gas pedal…if it is the differential you should hear a change in the pitch of the noise…since you are applying pressure to the gears then letting off. I noticed that there was a tapping noise in the front end when I let off the gas. anyone have any idea. And if i brake while the car is making that noise, the breaks make an even worse screeching sound (but my breaks don’t squeal when my car is not). When I let off the gas, the noise will stop. If they smell gas, they should leave the area and then call for help because that can turn into a major disaster. I left with the museum wax and a heavy-duty frame hanger that had three nail anchor points for remounting the print. or if i were to get on the breaks it would go away. When I take my foot off the gas pedal, there is a loud clunking, rattling noise coming from the underside of my car. I can hear a click when it does this. It isn't much to worry about, my N/T with headers used to do this on deccel before I put a turbo/gm maf and tuned it. A steep uphill will work as a test ground too. You can replicate the sound, but you press the gas while applying the brakes to slow down the wheels to create false load on the suspension. Its only happen in 1st gear. If I accelerate quickly from 50-60 there's no rattling noisebut that's also because I get out of the RPM range too quickly. The noise started out faint and has progressed to almost a rattling sound over the course of about 6 months. 4 engine (including turbo), to eliminate the noise, one has to take off the head cover, and, removing one cam bearing cap at a time. I have had worn tierod ends and they make a noise too. This noise always occurs only around this RPM range. Just bought an 05 Titan 4x4. You may hear a rumbling or a roaring sound, or a loud hammering or knocking sound. When im pressing the gas for the first few seconds I can hear a small rattling/sputter noise. How Car Dealerships Rip You Off (The Truth) - Duration: 11. Let off your clutch pedal and listen to that rattling sound coming from what you think is your engine. If you race the engine a bit, then you can hear the noise when you let off of the gas. The car felt fine and didn't shutter or rev up or anything - but sounded like some sort of a noise. but it doesnt do it all the time. and when i let off my foot on gas pedal, i didn't hear any whining noise and when i let my foot on the gas pedal again, i can hear that noise again. Step on the clutch pedal to confirm it’s gone away. Skip to main content. Let the car go uphill, foot off the gas, just as you start to lose altitude hit the gas, see if you get the noise. It stops when I let off the gas or give it more gas. Low and behold there's my caliper shifting side to side. i hear it especially when i let off the gas in that range so. The other thing you want to check is the fan support bearing and the upper idler pulley. Is there a homemade variation of that tool you may know about, or would I be better off to go buy the part? Blake. At home, I lifted the frame off the wall. With the engine off, inspect the drive belts for tension, wear, and cracks. On the Colorado sounds very similar to the exhaust rattle sound. and once I let off againit is back. Transmission feels solid and smooth. Best way to test with the car rolling try to let it roll to a stop without applying the brake, 'then' hit the gas and see if you get that noise. Whenever I am pressing the gas pedal to spead up, then release the gas pedal I get a wierd metalic rattling noise from my engine. The A frame bracket that sheared off illuded me for a while, as the noise wasn't very noticeble when driving, just a low clunk, and wasn't able to be seen unless you laid right under the rear axle. 6 SOHC I hear this rattling noise from the motor. New clicks, rattles or ticking sounds may be indicators of things having more clearance than they should as a product of normal wear—often able to be adjusted. As soon as I came off the gas I heard a brief grind/squeak noise. Explorer, Sport Trac, Mountaineer & Aviator - Horrible grinding noise/vibration when letting off gas? - I have a 97 Explorer with about 150K miles on. Rumbling or Grinding Noise. Address the issue before more problems and costs arise. It just used to take forever to get there, and anything looking like an incline would cause the speed to start dropping quick. I've completely re-done my rear axle and suspension and it has taken me FOREVER to get it all back in the car due to lack of time. Use a regulated fill valve to stop noise like our 400AH PerforMAX® Fill Valve or the 400H PerforMAX® Toilet Fill Valve: PerforMAX® fill valves come with a regulator built into the valve to slow down the incoming water by reducing the speed by the incoming water we can stop the resonance noise that is occurring. And it only happens when I'm lightly accelerating. Once it was determined that the noise was the operation of the Runner Control we compared the operation of 3 in stock vehicles , all with 5. The noise matches my speed, rather than RPM. It stops if I let off the gas. and when i let off my foot on gas pedal, i didn't hear any whining noise and when i let my foot on the gas pedal again, i can hear that noise again. only happens when I let off the gas. Guys my 1992 NSX is have a weird issue, its never done this before, when I press the gas everything is normal, thru 0. The noise is barely audible while accelerating, but is very loud (as apparent in the video) mainly when the rpm's are coming down. I have been getting a rattling/metal clanging noise (hard to describe) when I am accelerating over 45mph. Reply; jbrodsky June 11th, 2018. It's not as loud at high speeds but still there. You can replicate the sound, but you press the gas while applying the brakes to slow down the wheels to create false load on the suspension. The noise I'm more worried seems to come from the back only when taking off or being in second at lower speeds. I don't remember exactly what causes the sound but years ago the problem was blamed on low octane gas. I just got a 2015 Toyota Camry. i have brand new u joints If you're convinced that it's inside the shaft, take it off and shake it. Yet any other time the engine is buttery smooth, cold idle, warm idle, acceleration, etc. as your slowly releasing the accelerator listen for a faint rattling noise. eg when driving in city traffic you take foot off accelerator to begin to slow down it start knocking noise but slops as soon as you touch the accelerator. I have the same issue with my 2010 103. The exhaust pipe and some other parts remain hot even after hours of switching the engine off. If I release my brake slowly and stop again esp at traffic lights, I can hear this creaking metallic sound coming from my rear, as if some hinges is not well oil. Thus, there also is no adjustment for valve clearance either. Hey everyone I have 2018 Accord 2. That noise goes away when the clutch is disengaged. After I put everything back together it was fine for about a month then it started making a rattling/vibrating noise when accelerating. The exhaust pipe and some other parts remain hot even after hours of switching the engine off. When I let off the gas the vibrating stopped. I noticed at slow speeds that when I let off the throttle to shift gears I hear a rattle in the motor. Really bad rattling sound upon deceleration. ) I immediately let off the gas, and then I can not reproduce the noise. The 2018 Ford F-150 has 1 problems reported for noise when you release gas pedal. People who get a rattle while accelerating or at a certain rpm most likely have a bad cat that is going to pieces on the inside. It was about $40 at NAPA. CarComplaints. the grinding noise can barely be heard from drivers seat but is very noticeable from passengers seat sounds like its coming from under passengers seat under. 2L I-6 Engine and Drivetrain > 4x4 Drivetrain > [SOLVED] Weird Noise From Front Left Tire When I Let Off The Gas. while on the the throttle i dont hear it. Before that, you don't hear anything but wind noise but, the rattling/click type sound happens once the gas is let off. com : Baby Einstein Sea Dreams Soother Musical Crib Toy and Sound Machine, Newborns + : Baby. Let the car go uphill, foot off the gas, just as you start to lose altitude hit the gas, see if you get the noise. It idles quietly, and can drive under 45 mph. The sound doesn't get any louder at higher speeds and it doesn't make the sound when I let off the gas or break or push the gas pedal from the parked position. Yep, you have the very early beginnings of a heat shield rattle. the grinding noise can barely be heard from drivers seat but is very noticeable from passengers seat sounds like its coming from under passengers seat under. Then i heard this rattling noise in my engine area. lifter but im not sure. One thing I forgot to mention, today on the way home, when it was making the noise at idle, 2 or 3 times I got it to stop making the noise by popping it into neutral or park and then back to drive. " So we tested another in the lot when I picked it up and under accelerate while not moving on an off the gas you do hear a plastic valve open and close. The noise doesn't really seem like the sound a turbo wastegate makes -- it's more like the sound of fluid running through a hose. Any thoughts would be appreicated! See the video for the noise. It only makes noise while coasting or stopping and only sometimes. I took top off and with the dryer running pushed down on the drum and the noise returned. I only noticed the noise two nights. thx! Just get underneath your truck and see if you can wiggle the driveshaft where the two parts join together. You'll know for sure then. I find this nice for some situations and very irritating for others. It strangely disappears as soon as you let off the gas, and you might not hear it at all on light acceleration. You need to check the vehicle for an air leak, (maybe a vacuum hose come off), oxygen sensor on bank 2 not working, or a knock sensor having failed. Is this something to be concerned about? Second, I notice the little tool in the picture to lock the sprockets in unison. Car Problems With a Rattling Sound When Accelerating by Robert Moore Rattling noise during acceleration can be caused by several different but common failures, including loose heat shields, bad belt pulleys and ignition pinging. Invariably though, it pays to be in tune with noises that appear in your Land Rover, to prevent things becoming more costly in a month or so. I only hear this rattle when I give it gas and then sometimes it makes no sound. When I am driving anywhere over 40mph and I completely let off the gas pedalI get this really loud rumbling noise and it shakes the jeep pretty good. Today the check engine light turn on and I don't hear the noise anymore?. It ONLY happens when pressing the gas to accelerate. It sounds like its coming from right under the rear seats. Initially I thought it was coming from the clutch, since I associated it with pressing the clutch and letting off the gas, but then I found that I got the same noise from letting off the gas without disengaging the clutch. As soon as I hear it I can let off the gas and it will stop, but if I hit the gas again it will continue. I have been noticing a bad rattle and vibration when I let off the gas pedal going down the road. The first day the light came on was very humid here (live in Arkansas). I now definitely hear it when letting off the gas petal AND when applying the brakes. Try this and let me know if you hear it too, from a stop roll up your windows and turn your music off. It does not sound at all like air, it sounds metalic (I think). I have a rattle when letting off the gas. I can hear a click when it does this. Put new muffler on a Honda Foreman but getting a Rattling sound when let off the gas. Happens every morning when I put it in reverse and back out of the garage with moderate pressure on the brake. Plates will be replaced and rear diff. They replaced the entire engine/transmission under warranty. If you blip the gas it will go away immediatily then come back 10-15 sec later. You'll know for sure then. It also way as soon as I let off the gas pedal, could it be a cable or a gear of some sort into the transmission although the speedometer is working fine also so I am not sure. The sound "IS" effected by rpm if downshifting and letting off the gas normal engine/trans deceleration, but seems most effected by the speed of the car. I will have to investigate further. The other thing you want to check is the fan support bearing and the upper idler pulley. At around 50 mph when i let off the gas i hear a horrible grinding/whining noise and i feel the floor vibrating. Promaster has the 3. It's actually a similar sound to that what you get when braking to a stop (the last couple MPH) on a curve and downhill. We’ve had three different plumbers out. Going down the road yesterday I noticed my truck had a rattle when accelerating and it stops when you let off the pedal. If I accelerate quickly from 50-60 there's no rattling noisebut that's also because I get out of the RPM range too quickly. I have been getting a rattling/metal clanging noise (hard to describe) when I am accelerating over 45mph. Its not my tires because the sound stops when I stop coasting. Try this and let me know if you hear it too, from a stop roll up your windows and turn your music off. There is an abnormal engine "rattle" noise when decelerating (letting off throttle) between 1000 and 2000 rpms. Ok so I went out and played around a little more on it today and when going slow and let off the gas it makes a clunking sound. I intend to by a mic for my recorder and install it under the tank, because it sounds like it's coming from underneath my tank as well. I've noticed that, especially in first gear, the car makes an odd noise when I take my foot off the accelerator. Its crazy at what these heat shields can sound like. Anyone else have this? Know what could be causing it?. Will try to describe it here. Power is normal. Download Gas Pump Off sounds 158 stock sound clips starting at $2. i do see a little abount of fluid (small leak) where the slip yoke slides into the back of the t case so im. At speed, the sound either goes away or is masked by road noise. Today on the way home from school, I noticed that if I let off the gas, the card had a vibration in it. Is there a homemade variation of that tool you may know about, or would I be better off to go buy the part? Blake. I know my car's motor runs louder than some but this rattle is something completely different. all you gurus I need suggestions. The noise I'm more worried seems to come from the back only when taking off or being in second at lower speeds. As the title says, I've got a weird rattle (but no shake) when letting off the gas while im in gear, this only happens under about 30 mph and 2end gear. Could this be an output shaft bearing going south!! The cart is very quiet when driving no noise. ok, bad u joints will only clunk when you step on the gas or when you let off the gas or on hard shifts. Creaking and Popping in the Night The many materials that make up your house — wood framing, plywood, glass, metal ducts, nails, plumbing pipes — all expand and contract at different rates. Where is the rattling noise coming from? The first step toward dealing with a rattling noise in your car is to identify where it's coming from. Should be changed at least every 30K miles IMHO. When these go bad then will setup a rattle at idle and low rpms that is close to an injector rattle in sound. I noticed yesterday that my CRV is making a rumbling/rattling noise when I am going over 10km/p. When get into the gas a little bit and then let off there is a disticnt whining noise. And it only happens when I'm lightly accelerating. Yeah I would classify mine as a grumble as I let off the gas as you mentioned. Four days later I was operating on a city street when the same type noise occurred. In 2wd, 4wd high and low. Average failure mileage is 3,150 miles. I only noticed the noise two nights. ive notice if i push in the clutch it goes away. The knocking / rattle happens when I let off the gas and the truck enters V4 for mode. only happens when I let off the gas. Find out what that might mean in our guide to diagnosing problems based on naughty noises. But some of those problems may be urgent and rapid response may prevent or minimize potential damage. As Rev said I put enough pressure on the Dealer and Kia Canada that they decided that this was going to be the fix and it was. 2 days ago it was very humid and the light came on again and I can hear the noise. They replaced the entire engine/transmission under warranty. Its a single knock when letting off the gas or when punching the gas. Took the belt off and still. But as soon as I ever so gently touch the gas pedalit goes away. When I let off the gas the vibrating stopped. When a house cools at night, these materials may move slightly, rubbing against each other and making noises. So I let off the gas and I hear the rattle and as soon as I press on the gas again it stops. I have a 2001 Toyota Corolla with 140,000+ miles, 4 cylinder, automatic, 1. 4 Lose bolts you hear rattle after you rev and let off, of course need to be tightened. Only happens when im traveling 45 to 50 mph area. I've got a 2011 Expedition with about 120k miles. Car Making Noise when Turning Right? Ok so with all the snow we got this weekend, I have a hard time finding parking on the street. The offense ran smoothly — though it did seem to lay off the gas in the second half — the defense won the turnover battle and shut down any and all SEMO attacks, and the special teams finally. Dealer says heat shield issue. Just bought a '01 Forester, manual transmission with 190,000 miles, shifts well through the gears but driving straight down the road it has a clunking noise while accelerating, when you let off the gas pedal the clunking stops, accelerating again the clunking comes back. The only conclusive cause-effect relationship I have observed is that when the engine is cold (blue light on), the rattle doesn't manifest itself. Subtle enough that nobody else would have ever noticed it. Coming down from 2600rpm till about 1400rpm, there is a high pitched chirping. I am hearing a clunking/knocking noise when I accelerate and decelerate, especially in lower gears. Then i heard this rattling noise in my engine area. I let my car warm up for 5-10 minutes. I noticed yesterday that my CRV is making a rumbling/rattling noise when I am going over 10km/p. Shop; If the clearance opens up, the valve lifters will rattle off the valve tops. New clicks, rattles or ticking sounds may be indicators of things having more clearance than they should as a product of normal wear—often able to be adjusted. The first time it happened it sounded just like a rock had been kicked up and bounced off the underside of the truck. I thought it was just something in the truck that was loose so I never really worried about it. Nope, it is in 2wd high. known issue: cats rattling When the engine is warm, I get a rotational rattling sound after I let off the gas and the revs are around 1500-2000. With no noises. Engine Rattling And Whining Sounds problem of the 1997 Ford Explorer 19 Failure Date: 06/02/2001 Timing chain was making a rattle noise and we had it checked out and they said that they had a safety recall. Transmission feels solid and smooth. It stops when I let off the gas or give it more gas. Seems to do it all the time under those no load conditions but seems more noticable at like 25-30 mph and I try it. Coming down from 2600rpm till about 1400rpm, there is a high pitched chirping. I don't have a rattle under load just when giving it gas and then a deceleration rattle. Thread: rumbling vibration when letting off the gas pedal at highway speeds. Power is normal. Unique problem - 2001 s40 front shakes at around 30 mph and up but only upon acceleration. the grinding noise can barely be heard from drivers seat but is very noticeable from passengers seat sounds like its coming from under passengers seat under. Worn or otherwise compromised drive belts are a common cause of noises when accelerating. Yep, you have the very early beginnings of a heat shield rattle. At around 50 mph when i let off the gas i hear a horrible grinding/whining noise and i feel the floor vibrating. Kinda sounds like a rattling heat shield when driving. The first day the light came on was very humid here (live in Arkansas). My car shut down with me while driving, when I open the hood and check the oil it didn't have oil I put some oil in the car when I start it back up I hear a loud ticking noise I leave it for a minute, and drive it for like 30second and stop I turn the ignition off I turn it back on I hear the same loud noise when I press the gas pedal the car. More of a vibration shakenot like a death wobble shake. backfire/rattling noise? gas but when i let off there is a lot of backfire noise that sort of sounds like a piece of my exhaust is loose i guess is the best way. Does not make this noise when truck is in Park. Rattling — Frequent rattling or vibration-like sounds could be caused by loose components or unsecured ducts. If I hit a bump while slowing it usually starts making the sound. Its a single knock when letting off the gas or when punching the gas. It's not a deep "gears grinding" noise but more of a thinner metal rattling/grinding on something. I have a rattle when letting off the gas. It stops instantly when the engine is turned off. Where is the rattling noise coming from? The first step toward dealing with a rattling noise in your car is to identify where it's coming from. Could this be an output shaft bearing going south!! The cart is very quiet when driving no noise. i do see a little abount of fluid (small leak) where the slip yoke slides into the back of the t case so im. Let off the pedal, be sure that whirling sort of rattling sound is gone and know that a new throwout bearing is in your immediate future. As soon as the vibration starts, you can let off the gas or step on the gas to change the RPMs and it instantly stops. but its very annoying. This is a safety issue and needs to be addressed by an HVAC professional. When I let off of the gas pedal the noise stops. This happened off and on for the rest of the 30 min drive. This has been a frequent complaint from 2018 Ford F-150 owners with V8 5. If I accelerate quickly from 50-60 there's no rattling noisebut that's also because I get out of the RPM range too quickly. metal grinding/rattle form the engine bay around 1-3K RPM in first gear, sometimes in second. The 4-wheeler has always made a clicking or chattering sound when you give it gas. fluid will be drained/refilled. Posted By: Trav Re: 1KR-FE engine rattle noise under load - 10/05/14. The other noise is more grumbly (low in tone) which feels like it's in the diff or something. thx! Just get underneath your truck and see if you can wiggle the driveshaft where the two parts join together. A Roaring Sound That Increases With the Car’s Acceleration. sounds like a rotation grind - you let off the gas. But since it goes away, it could very well be that the exhaust manifold isn't sealing right when cold and it needs to heat up and expand to seal. I noticed that there was a tapping noise in the front end when I let off the gas. When I'm driving, the gears shift fine. 0T 32K on the newly installed used (2010 engine). Its a very rapid noise and the speed of the noise seems to go with engine speed. I strongly suggest the source of the noise is located and rectified as a priority before worrying about anything else. I have also got it to stop, or start, by playing with the gas pedal. But all suspenion parts have been checked at the dealer and are good. It sounds something like somebody wrapped a zip tie around the driveshaft. It does not sound at all like air, it sounds metalic (I think). Is this something to be concerned about? Second, I notice the little tool in the picture to lock the sprockets in unison. "Down Idle" noise.