HELP! Been to 3 mechanics. Two that are GM dealers. and I have gotten 3 different answers, from its normal to it needs a high pressure fuel pump. Car runs good. But when it is warm, not cold, I get a mild knocking sound when at the lower RPM range. 1000 to 2000 RPM. I don't hear it while in neutral and revving the engine, but when accelerating in gear from a stop I hear it. I can also get the knocking noise to happen while power braking it. The slower I accelerate, I hear it more. 2012 with 50k miles, Bought it a few weeks ago, went on a trip, got home, then I noticed it. Oil is correct. One GM guy said he hears it but nothing he can do. Said engine is fine. Other GM guy said it needs the high pressure fuel pump??? Its like $500 dollars. Could a HP fuel pump make a knocking noise, while warm only, and still work fine and not leak. I have been bashing my brain for 2 weeks now trying to figure this out. I wend and drop 2 other Traverses, that did not make that noise, so I know its not normal. And I don't think its the noise that injectors make. Any ideas would be helpful. Not a CV axle, does it straight ahead as well. thx.
Knocking sound when accelerating from a stop or low RPM.
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I bought a 2011 1LT back in september. I would hear a thudding/rattling noise when going over small road bumps and when braking/accelerating. I took it back to the dealer 2 weeks after i bought it and it turns out both front struts needed replaced. They replaced them at no charge and have not heard the noise since. The tech that worked on it said the struts go out on these all the time. Hope this helps.
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You may want to check your motor mounts for a worn condition.
From a stop or low revs, the mounts are reacting to the engine under torque. When it is in park or neutral, the engine is not transmitting the torque to the mounts/engine cradle.
From a stop or low revs, the mounts are reacting to the engine under torque. When it is in park or neutral, the engine is not transmitting the torque to the mounts/engine cradle.
Ok, How do you check those. ? Was told that it could be a high pressure fuel pump malfunctioning, but it still runs good and has power and no leaks. That was the dealer. Another mechanic said these engine have a problem with building carbon on the intake valves and then the build up slaps against the valve guide. Sounds logical as well. I don't think it is the mounts, because once it hits 1500 RPM it continues to knock slightly in gear while power braking. I have had 3 different mechanics look at it with 3 differnet opinions. I know these fuel pumps tick and I hear that at idle, but this is more of a knocking sound that goes away at higher RPMs.XRDreamliner said:
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Typical engine term "knock" refers to improper detonation in the cylinder caused by gas that is too low in octane for the compression ratio often experienced under low rpm/high load conditions, e.g., a forced downshift going up a hill....a second or two might be normal......ECM operates the engine under optimum spark advance to prevent knocking and engines have anti-knock sensors that "hear" the knock and immediately retard the spark to prevent a further knocking condition......try higher octane gas to see if it improves the condition, if it improves something is fluky with the knock sensor settings or circuitry or you were formerly using gas not meeting the engine's octane requirements.davemcsjr said:
I have been reading "engine noise" posts, I have 2012 and have a rattle/knocking sound when accelerating from stop. I can also brake torque it to duplicate. Drove other 2012's no noise. Dealer has confirmed as abnormal and has been great about trying to resolve but after 5 times back and 2 pages of parts I still have noise
I would describe as more like a bearing rattle. I have new frt exhaust pipe, both new frt axles, new frt mtr mount, new intake manifold, and after the last time of a 1 1/2 week drop off they basically overhauled my engine with new pistons/rods/brgs-timing chain etc.
Noise is still there.
Let me first say the dealer has been Great and has involved Technical Assistance for direction but to no avai
I'm waiting for a field engineer to inspect in person.
I would describe as more like a bearing rattle. I have new frt exhaust pipe, both new frt axles, new frt mtr mount, new intake manifold, and after the last time of a 1 1/2 week drop off they basically overhauled my engine with new pistons/rods/brgs-timing chain etc.
Noise is still there.
Let me first say the dealer has been Great and has involved Technical Assistance for direction but to no avai
I'm waiting for a field engineer to inspect in person.
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Maybe the rattle is not in the engine. Another thing to check would be further down the exhaust system, could be the cat converter or the heat shield......no idea if GM is still using ceramic "biscuits" embedded with catalyst materials, but when those break apart you'll get a rattle, likewise a bent or loose heat shield over the converter.sheck327 said:
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Hello sheck327,sheck327 said:
We’re sorry to hear that you’ve been experiencing this knocking sound in your Traverse and sincerely apologize for any inconveniences caused. It does sound that the dealership has done their due diligence, and that the appropriate parties are working to resolve your concern. However, if you would like any additional assistance please do not hesitate to reach out to us by private message. Please be sure to include your VIN, contact information, mileage and dealership to be documented.
Helen
Chevrolet Customer Care
I have a 2012 Acadia that is making this same described noise. Has anyone correctly diagnosed this noise? TDK
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I have a 2012 traverse with new timing chain making a knocking noise that is not consistent and get the p062f code occasionally also. I would appreciate any help with this issue as we are low on funds and spent a lot replacing the timing chain and do not have the money to take the car to a dealership as it is out of warranty. It seems like there are a lot of issues with this engine and it is disappointing to have a Chevy with so many problems after only 130,000 miles. Every other Chevy and Buick I have owned has had or has a lot more miles without serious problems.
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I have a 2019 Buick Enclave they said that the high pressure fuel pump makes a noise and that is tru however the two noises are not the same,I wouldn't give them one red cent unless they put it in written that if this noise is still there they will issue you a full refund,but I doubt that the noise if from that pump it is from the engine and they want you to believe its normal or that it the fuel pump.
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