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Questions tagged [knock]

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Renault Clio 2007 1.2i ticking sound at one accelerator position

I have a Renault Clio 1.2i and the engine (I guess) makes a ticking sound only when accelerator is slightly pressed down (usually the location where I'd like to keep my speed and not accelerate), if I ...
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1answer
287 views

Rod knocking, out of oil, or both?

So, I had noticed what sounded like rod knocking in my 2004 Nissan 350z with 140k miles. IT got progressively worse, and I went to look around. I ended up finding all of my oil gone, seemingly due to ...
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0answers
30 views

knocking noise sounds like its coming from under my feet!

I have an 03 chevy cavalier. While out driving yesterday it started to make a loud knocking noise. It sounded like it was coming from under drivers feet area. It also got louder with acceleration. Not ...
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1answer
967 views

Bottom End Knock

I'm looking to purchase an engine with a bottom end knock, with the assumption that I will be able to rebuild it with no previous experience, fitting aftermarket forged parts. These are my ...
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0answers
686 views

Can knocking noises caused by anti roll drop links be intermittent or just not detectable until they get worse?

So I was getting a knocking noise from under car and mechanic 1(who just had axle stands i.e. no ramp) said its either the anti roll bar or ball joint and there was no way of knowing which you just ...
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4answers
2k views

Can exhaust problems cause a knocking sound in anyway?

I have an extremely lowered car, the exhaust pipe moves, squeaks and clanks at times. The sounds are not so bad on smooth surface roads. I had been getting a knocking sound from under car and just ...
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3answers
117 views

What is exhaust gas recirculation?

From what I understand, EGR is used to reduce the temperature of combustion without increasing the amount of fuel injected to reduce NOx emission. This is done by reducing the oxygen percentage ...
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1answer
3k views

Knocking sound from under car when going slow, what are the likely causes?

I am getting a knocking car from under my car. It seems to be under the clutch and on the left of it(note we use right hand drive). The knocking sound is noticeable when you drive slowly e.g. moving ...
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1answer
264 views

Sudden pop when turning, what could be cause?

I have an old civic em1 1999. The car has recently been making a knocking noise from underneath and infront of the clutch area it seems. Showed it to a mechanic he said it was most likely anti roll ...
2
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2answers
1k views

Drove over a semi-large rock and now vehicle vibrates in Park - Goes away in Drive

So... I hit a rock pretty bad over the weekend :(. I was going about 100KM/h maybe less, and it was smaller then a basketball sized rock, but it did some damage and jolted me/vehicle. I immediately ...
1
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1answer
524 views

Engine knocKing noise…please help

I have an engine knock in my 04 holden rodeo with the 3.5l petrol 6ve1 engine. Seems to knock on idle dissapears with acceleration.(or just gets muffles by exhaust noise) any help on attempting to ...
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2answers
10k views

If a car has a rod knock what is no good the head or the block?

Wondering if the block or head can still be used?
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0answers
115 views

Diagnosing Engine Knock

My 2003 Volvo XC70 had a slight engine knock for about 5000 miles but never showed any signs of damage to the engine. Oil was fine and it only made the sound in around the 2500-3500 rpm range. One ...
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0answers
653 views

Engine knock when engine is hot

I have an 05 Mazda MPV V6 engine. When it starts up there is no noise and everything is fine. After engine is hot I get a knocking sound and the oil pressure light comes on. By looking at earlier post ...
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2answers
146 views

Oil change: level was so low it didn't show on the dip-stick?

Had the oil changed and they said it didn't show on the dip-stick. Now it seems like the engine could be knocking a little. Could it be damaged? confused
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2answers
30k views

Knocking/clunking sound coming from back end on flat road

I drive a 2014 Mitsubishi RVR and for a couple of months now there has been a knocking noise coming from the back end of the vehicle. At first it was very faint and you could only hear it when the ...
3
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2answers
1k views

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 ...
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2answers
5k views

Why is my car making a knocking noise?

2001 Chrysler Sebring lxi 4 door. 2.7 liter 24 valveWhy is my car making a knocking noise? It will start it, drive yet when i press the gas it makes a knocking sound and takes off very slow
1
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1answer
124 views

Knocking in a 1970 Dauntless V6

I have a low freq knocking, about 6 to 10 knocks, very loud on startup until oil pressure comes up. Knocking quiets down and engine runs well with no knocking but then returns at idle as oil pressure ...
4
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1answer
1k views

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....
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1answer
237 views

What are the possible reasons for an Engine Knock?

I have a Perodua Viva Elite (2011 MT). Several months back my vehicle engine started to knock and Engine Check Light started showing up while driving in traffic. So I went for an Injector replacement, ...
6
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3answers
474 views

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 ...
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2answers
3k views

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 ...
2
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0answers
172 views

Engine knock due to contaminated cylinder, is there a way to purge? 1998 Ford F-150 4.6L

I am an apprentice for a small shop and we recently replaced a 4.6L engine on a 1998 F-150 due to knocking problems (important). The engine we swapped it for was presumably in good running condition, ...
3
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0answers
1k views

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 ...
3
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0answers
713 views

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 ...
5
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3answers
3k views

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?
9
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2answers
133k views

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 ...
2
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0answers
95 views

Possible engine knock in 1995 GMC Jimmy

Hello I have a 1995 GMC Jimmy (Automatic & 4x4)and I have been working on it on and off for about a year and a half, i have fixed many things with it but there are couple things that I have not ...
5
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1answer
542 views

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. ...
2
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1answer
1k views

Bad exhaust leak or valve interference after HG change?

2006 Volvo s40 2.4i I replaced my HG the other day (I've done a few before with no problems). I was very careful marking everything. Locking the cams together with a cam locking tool specific for ...
1
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1answer
108 views

How can I tell if I would benefit from higher octane fuel?

Given the number of variables involved in whether an engine will knock on a given fuel in a given environment: How can an end user determine whether the engine is retarding timing due to fuel octane? ...
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2answers
1k views

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 ...
3
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1answer
6k views

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 ...
1
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1answer
81 views

x3 bmw latest model has a diesel knock, opened the top one piston not reaching tdc

I have an x3 diesel latest model bought it at an auction. Now it had a heavy diesel knock sound. So I decided to open the top. When I did, I saw neither visual damage on my injectors nor the cylinder ...
5
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3answers
2k views

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 ...
3
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1answer
1k views

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 ...
5
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2answers
173 views

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 ...