Motor Vehicle Maintenance & Repair Stack Exchange
Motor Vehicle Maintenance & Repair Stack Exchange

Questions tagged [knock]

40 questions
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How can I be sure that a rod knock is actually a rod knocking?

I have a 2005 Ford Escape 2.3 L engine, there is a knocking type sound as soon as the engine is started and the speed of the "knocking" follows the RPM. How can I be sure that it is in fact a rod knocking and not something else?
A.StetzSr
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Knocking valve sound after gasket replacement

I changed the intake gaskets top and bottom along with valve cover gaskets on my Ford F-150. After I finished it was hard getting started but I finally got it started and now it sounds like the valves are knocking. I changed the oil, but they still…
Tony Brown
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2003 Dodge Ram 1500 3.7 engine knock

My truck has been making a knocking noise upon acceleration. Today the knocking is constant and louder. What could this be? Pistons? Oil sludge? New motor?
ablank13
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Van makes knocking noise, even after it has been off for hours

I have an '05 Sienna. At 7 this morning, it was making a knocking noise when I went to leave for work. It had been off since about 9:30 last night. Clicked unlock on the remote and nothing happened. Had to unlock it with the key. Internal unlock…
Kevin
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How often does my engine check fuel octane?

I have an Acura TL, which specifies "premium" fuel. However, I know that the engine has anti-knock sensors that retard timing to prevent detonation if somebody accidentally fills it with lower-octane fuel. How does the ECU decide when to try…
feetwet
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Honda FIT GP1 HYBRID 2011 knock

in my auto gear honda fit gp1 hybrid car, (mileage 56 000 KM) I had a engine tune up and changed my injectors (8 injectors) last month and after 2 weeks i started getting a slight knock (jerk or shaking). i remember i have had this once or twice in…
user9059
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2 answers

Is it common for ECU's to maintain individual limit maps for each knock sensor?

Preamble I'm in the process of interpreting my BMW M5's ECU binary with the aid of some nifty scripting and rather informative forum posts. One of the things I've found is that there are knock limit maps for each cylinder. While this is somewhat…
Zaid
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What is this knocking noise in my 2002 Corolla?

* Skip to second paragraph for details on the noise * Hi all. My other half's nephew left for the Philippines for a vacay, and asked that I look into a noise that has developed recently in his Corolla. This forum has helped me numerous times so…
Nathaniel Davidson
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Knocking under load on first gear

I have this issue.. I already asked on FordOwnersClub, but I feel like here I might have a better chance to sort it out. I bought a Ford Focus mk3 2011 with 1.6 ecoboost 134kW engine with 90k km. My issue is, that under heavy load (heavy…
h00ki
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What will happen if the knock sensor fails?

I have understood that most recent cars have a knock sensor. This allows among other things greater timing advance due to detecting knock in case the fuel doesn't work well with a greatly advanced timing. Now, what will happen if the knock sensor…
juhist
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02' GMC Envoy. Engine KNOCK, not rod knock

I have a 2002 GMC Envoy. Last year it developed a knocking that was at a very low volume but became louder in a 2 week span. After that it's been the same, it's louder when the engine starts cold and then becomes quieter when getting hotter; still…
Omar Gonzalez
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What else should be changed if I already have the oil pan off for cleaning?

I have a 2005 Chevy Suburban 1500 4WD 5.3L with 187000+ miles. It has a really bad tapping/knocking sound. I think this is the infamous lifter knock, and was caused by infrequent oil changes and running low on oil about 100k miles ago. I am planning…
Nathan DeWitt
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Engine knocks and engine speed falls below idle upon releasing the throttle

I have this strange problem on my 1999 Volvo V40 1.9T T4 (B4194T engine, no VVT, ~150k miles), I'll try to provide a detailed description. I noticed that only when the engine is warm, whenever I drive at some RPM and release the throttle along with…
I have no idea what I'm doing
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2001 Toyota Sienna LE P0330 Error

I don't know much about cars, so I might get some terms wrong. My girlfriend drives an '01 Sienna LE and for a couple months the check engine light has been on. When I took the van to O'Reilly's and had them check the computer, it came back with the…
Cora
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Diagnosing pinging issue in 2003 Nissan Sentra

While under load, the engine sounds like there is a bunch of marbles bouncing around in the engine. Revving the engine in neutral does not create the noise. Filling the gas tank with 93 octane instead of 87 "solves" the issue with the noise. Filling…
stoj
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