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9

When you start the engine and you hear the sound, does it sound better after the vehicle is warmed up? A rod knock will only sound worse (louder) as the engine heats up. It will not go away as the engine gets warmer. If it does, it is probably something like an exhaust leak which closes itself as the engine manifolds get warm. The opposite could be true as ...


5

Pinging is caused by one of several different reasons. It is usually a hot spot in the combustion chamber which is causing the issue. A hot spot is usually made of carbon buildup, the edges of which get hot very easily, will glow red as such, and will ignite the air/fuel mixture. If a hot spot is present, it will pre-ignite the air/fuel mixture during ...


4

Sometimes it is hard to tell the difference between a rod knock, wrist pin or piston slap in the early stages even when using a mechanics stethoscope. A main knock is a deeper sound that is more pronounced at the bottom of the block as apposed to the top when using a stethoscope. Hard knocks that happen at startup and go away quickly are a sure sign it is ...


3

The 3.7 is notorious for having a rocker arm fall off and or lifters collapsing. This is usually accompanied by a check engine light being illuminated. Use a stethoscope or a long screw driver and try to isolate where the knock is coming from. If it's coming from a valve cover, remove the valve cover and you're likely to find a rocker laying around. If ...


3

There's no way to tell for sure, but since a true "rod knock" has nothing to do with the block or the head, you could most likely reuse both of them. You'd probably want to do some work to them to ensure they are in good enough shape, but that's another question/answer. EDIT: Here's an answer describing rod knock.


3

It's possible but unlikely that the engine mounts are the problem, at least they wouldn't be the only problem that needs to be addressed. An engine mount is a flexible cushion that connects the engine to the car frame, they degrade over time and it's possible that an impact could break one loose, especially if its closer to the end of its service life. That ...


3

It sounds like the shutting mechanism for the door is not quite getting the door closed, or maybe the switch which tells the door closer to do its thing is broke. As @NateEldredge says, get the battery recharged completely and investigate further. Once it's recharged, try to open and close the door from the side the noise is coming from (assuming it has two ...


3

The ECU(or at least the better ones) can indeed actively 'search' for the point of pinging as you said. The pinging sensor listens to the combustion, based on that the ECU determines how close it is to knocking. Real, actual knocking is audible even to the untrained human ear, but knock sensors can also detect near knocking situations. And that is the most ...


3

Yes, it is quite common. I initially said that it isn't, but I was wrong. I had another look at my Subaru's mapping and saw that there are more ignition timing tables than I first thought. Here's a complete list of tables (note the greyed out ones): Factors that could warrant separate knock maps for each cylinder would include the following: differences in ...


2

I don't think you replaced the injectors. I think you replaced the spark plugs. Injectors are what spray gas into the combustion chamber, and those are usually replaced or cleaned on older cars. You said it happened right after the spark plugs were replaced. Why not replace them again? They might be the wrong spark plugs, they might have the wrong spark ...


2

The only sensors used to determine fuel quality are the knock and mixture (Oxygen) sensors. The adjustments are continuous whenever the engine is running. The vehicles I have experience with, this includes your Acura, all use this method. This method is accurate and not especially challenging from an engineering perspective. Attempts in the past to ...


2

It is more than likely not the sensor. The problem lies in the circuit which goes to the sensor. Replacing the sensor is probably the last thing I'd do in this case. In this case, I believe it is only a single wire you'd need to trace. It could also be the connector/connection at the sensor itself. In either case, it looks as though the intake manifold ...


2

Having a live scan running is by far the easiest way to tell if the ECU is pulling timing while the engine is running. Beyond that, you need to be aware of what the manufacturer's requirement for an engine is, such as it's performance level. Several situations which call for higher octane: Turbo/Super charging High static compression ratio (10+:1) Both of ...


2

The 2001 Sebring with the 2.7 engine holds 5 quarts of oil. Sounds like you ran it out of oil. That would make the engine knock and do all kinds of bad things to the internal engine parts. If you added oil and it won't run correctly now, you probably have major engine damage. This means you will have to have the engine inspected and repaired/replaced. ...


2

Another thing it could be is a failing exhaust gasket between the header and the head. These types of leaks will exhibit the knocking sound, but often quiet when things warm up and expand. Sometimes they'll only make noise until things are warmed up. While not fool proof method, one way to detect this type of leak is to look for black soot emanating from ...


2

Because you can move it by hand means it can probably move enough to hit something. So, replace the supports holding the exhaust for stronger ones or fit 2 loops instead of 1. Did that on a car once - worked a treat. Another option to reduce movement will be to increase the number of support points so going from 3 to 4 or even 5 can help - you have to ...


2

If you can move the exhaust by hand, there are a few options: (Remember that your exhaust line is steel, which typically doesn't flex well.) You've lost a stud or a nut where the line meets the catalytic converter ("cat.") (Which is not an acronym and should never be written as "CAT.") Many aftermarket exhausts join pieces of the pipe together with clamps. ...


1

Your issue is probably connected with driveline. I will assume that it is rwd/4wd car as you are suspecting driveshaft problems. To diagnose whether it is driveshaft related problem, drive slowly next to a wall (road separators are good) in neutral and "measure" the frequency of the knocks by hearing. Differentials usually have a ratio from 1:2 to 1:4 so ...


1

it's usually the ball joint on the opposite side of the direction you turn in. If they go bad, they can freeze and you can get a pop as it unseizes. It could also be a cv axle but you would have probably felt that. They have a tendency to rock the car. Depending on the "Pop" (vague description really) it could in fact be a sway bar if the bushing is out ...


1

The problem was a bent crossmember touching the tranny. I was told I could continue to drive with it but would always have vibrations but it's under 300 to fix so I'm fixing it. Fingers crossed that the vibrations go away! Update: 300 CAD bill to fix crossmember ($120 part + 1hr labour) and noise is 100% gone! :)


1

When it comes to engine knocks, I like to verify the worst possible scenario 1st, and that is rod knock. From a professional view, if this is the cause of the knock, depending on the value of the vehicle, is a game changer for a lot of people. With the vehicle running and knocking, disable spark from each cylinder one at a time. If the noise suppresses ...


1

Generally, a "rod knock" occurs when the clearance between the connecting rod journal and the crankshaft rod journal is out of specifications. This can happen for numerous reasons; most common reasons are probably bearing failure, fastener failure, or some sort of physical damage. If it is truly rod knock, the engine block and heads can probably be reused. ...


1

any way to record and upload the sound it is making? Usually a knock does not happen when the engine is cold and at low / idle RPM. Have you kept up with changing your oil and did it run low last year? Did you see metal particulate clinging to the drain plug or dipstick? Is your oil pressure low or is it missing an oil gauge? If the noise lessens when it ...


1

Without oil the engine could be damaged, yes. Oil is essential to keeping your engine running and healthy. An engine knock can be a sign of problems so get it thoroughly checked out.


1

Visit a wheel alignment shop and ask them for an inspection. Usually, rubber bushings wear out causing metal to metal contact. Could be strut mount, trailing arm bushing, link bar, upper or lower control arm bushing, could be anything. Not even an experienced mechanic can know without looking umder there.


1

Most knock sensors in use today are microphones. The most common sensor type is a piezoelectric crystal type. Failure is detected by: 1 Testing the circuit during a power on self test. 2) watching for signal thresholds during normal engine knock producing operating conditions. Field testing is done with an oscilloscope and a hammer. A tap on the engine block ...


1

Kinda sounds like you lost the lower end of the engine. How much oil does the engine hold? If it holds 4qts and you had to add 4qts. It was most likely ran with out oil and took out the lower end(crankshaft main bearings and piston connecting rod bearings.) With the information you given that would be my guess. But you should take it to a shop if this is ...


1

If you still have knocking, it means that there is too much clearance somewhere. While you replaced the main crank and rod bearings - did you have the crankshaft ground and the new bearings matched the new sizes or did you just put new bearings around the old crank (not the best idea). A possible different solution is to fit a small electric pump to build ...


1

Turns out there is a billion out on this problem. I don't wanna play links but it's there. Inside of the intake there is a baffle that comes loose and creates this noise.


1

It was indeed an exhaust leak. One of the exhaust gaskets wasn't on one of the studs so it didn't seal properly. I fixed it and the knocking is gone. But it didn't get rid of the smoke completely, which is now confirmed as exhaust gases. I hope the manifold isn't warped.


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