Engine knocking???

So i've been using this 93 Chrysler lebaron v6 for awhile now. It has 184,000 miles, this spring its started making ticking sound, it would come and go and fade away as i drove faster. The car burns some oil, and when i put in more oil the ticking sound would just stop for awhile. Some days it just does't make that sound. Its aways worst when i first start the car, or sitting at a stop light and take off.

I wasn't going to take the car in to get looked at, or take apart the engine, just like i wasn't going to replace the rings to stop the oil. It simply wasn't worth it.

Well today i was driving home and it now started knocking on the highway, its a dull knocking sound, that is not constant, just like the ticking. Sometimes the knocking will stop suddenly, then start back up. It seems to fluctuate. If i stick my hand on top of the engine cover i think i can feel the bumping vibrations.

Like i said i'm not really interested in having this fixed. Unless its something cheap and easy i can do myself. The most i ever did was change sparkplugs, change a starter, and drop a tank to put in a new fuel pump.

Is there some way i can get it to last a little while longer even with the knocking?

Oh is there a final warning sign right before the enigne blows?

Anyone know of a v6 or general engine site forum or board that might be of help?

I'm not losing any oil pressure either.

It could be a number of things, I'd guess a wristpin loose. Or maybe something in the valve/lifter/pushrod area. A good engine shop can tell right off what it is.

Is there an easy way i can rule out a rod knocking or bearing?

Started the car up and let it idle a bit, its quite loud kinda sounds like electric sparks a bit now. As soon as i gave it some gas the sound went away, then came back but not as loud.

Maybe its detenation.

Oh is there a final warning sign right before the enigne blows?


Sadly it sounds like a bearing has gone.
If your lucky the knocking will get really, really loud for a short period before it fails. Depending on the bearing, and how badly it fails the engine may sieze, it may put a rod through the block, it may just run really rough for a few km's before expiring.

Sadly theres no way to find out untill it happens.
Best suggestion is buy another car, or replace the enigne.

Too late to replace the bearing? Or is it not worth it?

Too late to replace the bearing? Or is it not worth it?
Usually a by the time a bearing starts to knock, the bearing journal (thats the metal smooth metal surface upon which the bearing rotates) is already damaged.

can be scratched, scored, pitted, or be out-of-round.

If this has happened, the engine needs to be removed so the crankshaft can be removed and machined, usually all rod and/or main bearing journals are machined and polished, and new bearings installed.
Often the rods and bearing caps are resized, too.

IMO if you do all this work, you may as well rebuild the entire engine, or find a new/used one to install.

If you are VERY LUCKY, you may just be able to drop the pan, locate the loose bearing, remove it, polish the journal with fine emery paper (if its not badly damaged) and replace those 2 bearing shells. However, this is a gamble, the knock may return soon.

Trying to piece this together,

Ticking that comes and goes, high mileage, burn some oil, ticking since spring, adding oil stops ticking, worse wwhen cold start or when taking off from light,

Now is knocking, starts and stops, not constant, no oil pressure loss. sounds like sparks, detonation still coming and going.


It really could be detonation, or a pin/piston or a shaft endplay. A bearing probably will not last a long time and usually is hard to make conme and go like you describe. If the ticking from before and the knocking now is the same noise I'd still look towards a pin/piston that finally broke or something in the valvetrain/lifter/pushrod? I don't know this specific engine, does it have push rods?

Detonation sounds like 1 or more marbles rattling in a can (lots of cars detonate when pushed) A piston/pin will sound almost like a double knock/tick (almost like a two stroke) Valvetrain,lifter/pushrods is just a single ticking. A bearing will vary with load and can sometimes be made to go away if the load is right, but will may not be as sporadic as you describe unless it is the endplay on the crank.

A couple things to try might be to drop into forward and or reverse when revving slightly to see just when it's the worst. Pull plug out to look at them, pull valve cover off and run it to check for top-end knocks. As I said before a good engine shop can probably "guess" what is knocking on the specific engine or can just simply hear it becayuse they do so many of them.

In any case you are real close to needing a rebuild anyways because of oil presssure and mileage.

I hope it is something in top like extra clearance or detonation. :licka:

Okay so when i rev the engine to 2000 rpms, there is a pause, then it sounds like tap dancing, or a machine gun. Very eradic though.

If anyone want to hear it let me know.

diagnosing noises on a forum is kinda like explaining to a blind person what the color blue looks like.

It could definitely be a lot of things. It could definitely be the last leg for the engine. Its most likely something that is not cheap.

Just drive it. If it blows, it blows. If you really want to find out more about it, take it to a shop and have an experienced mechanic take a listen to it. He'd probably be able to narrow it down at least, and it would probably cost you very little

No one mentioned exhaust leak, it can also be a ticking. Worst when cold, and possibly non-existant when warmed up. Probably not your problem, but easy to check by plugging tail pipe and start engine cold.

The car is not worth paying for a diagnostic test. I wouldn't get it fixed anyways, i'm quite sure its something not easy and cheap.

I'm just wondering how long it will last as is. Say if i keep it at 35 and off the highway.

my shop offers a free inspection with an oil change. Oil change cost $20.

Many shops will offer something simular.

Is this worth a cheap oil change and a free inspection? Since you're concerned enough to ask a forum about it, I would assume it is....

I just drove it around the block a few times, its not bad when i'm crusing, but when i step on the brakes or take off its louder and more constant noise. I does kind of sound like slapping when i'm driving, i get like three quick slaps in a row, some silence, then four quick slaps. Pulled in the drive way, then i got a constant double knock. This thing is just so random.

So do places like lube stop offer a free inspection with oil change? I'll have to run through the coupons and flyers and see.

no, you want a full service shop. Lube shops don't usually have "mechanics"

just drive around in your area and look for independant shops, most offer some type of cheap oil change and free inspection. Its a common way to get people into the shop....cheap advertising, if you will. Its why we do it.

I didn't know if they have diagnotic machine or not.

The full service shops are notorious around here. They always want $100 to hook in up to the machine.

I didn't know if they have diagnotic machine or not.

there isn't much of a "diagnostic machine" for engine noises. An ear, a stethoscope. The experience is what diagnoses noises.

I can tell a rod knock from a water pump bearing, to a valve tappet from an exhaust leak, usually without even opening the hood. Its not difficult, you just need to find someone who is familiar with the different sounds.

The full service shops are notorious around here. They always want $100 to hook in up to the machine.

Yup, thats what we charge. $80-120 for "real" diagnostics.

Yup, thats what we charge. $80-120 for "real" diagnostics.

I mean we have had problems with several shops around here. People always ask if you know somebody, and they keep getting told "i can't recommend anyone around here" thats how things are.

just to explain this better, there is no such thing as "the machine you hook the car up to". This is a common belief, that there is no human interaction in diagnosing problems.

There are tools that we use to help us to diagnose problems, no matter what it is, but the MAIN thing that is actually diagnosing things correctly, is the mechanic. A "machine" might give us the code stored in the computer, but that does you nothing if you can't translate that code(s) into possible causes, and know how to go about narrowing down the number of possible causes.

It takes experience, knowledge and a sharp mind to diagnose complex machinary. THAT...is what you are really paying for when you pay a shop to diagnose a problem. The mechanics brains.

But....$30K worth of equipment definitely helps.

I mean we have had problems with several shops around here. People always ask if you know somebody, and they keep getting told "i can't recommend anyone around here" thats how things are.

dude! You're making this $20 oil change sound like a really big investment!

There is definitely plenty of bad experiences people have with shops. I don't know of any shop that every customer leaves happy, or even a high ratio. Its the nature of the business.

I guess you should blow up the car since you can't get a solid recommendation on where to get your oil changed?

Wait a minute... Let's all get some more info before we condemn this car to death :)

Can you elaborate on the sound...

Is it a knock like someone hitting the engine with a mallet?
Is it a ping like detonation?
Is it a tick that is always there cold, but only sometimes hot?
Is it a snick snick that comes and goes all the time?

dude! You're making this $20 oil change sound like a really big investment!

There is definitely plenty of bad experiences people have with shops. I don't know of any shop that every customer leaves happy, or even a high ratio. Its the nature of the business.

I guess you should blow up the car since you can't get a solid recommendation on where to get your oil changed?

I'm just saying that i have had problems with all the shops around my area. If i want someone to look at it, i'll have drive a while and it may not even make it.

i think thermite would easily solve the problem with your engine.

Wait a minute... Let's all get some more info before we condemn this car to death :)

Can you elaborate on the sound...

Is it a knock like someone hitting the engine with a mallet?
Is it a ping like detonation?
Is it a tick that is always there cold, but only sometimes hot?
Is it a snick snick that comes and goes all the time?

Nothing sounded like hitting the engine like a mallet.
When i first start it up it sounds like someone is quickly knocking on a wood door. Then when i start driving its more of a pinging sound and switches between pings, ticks and snick snick, with pauses of silence in between.
When i'm sitting at a light it goes back to the knock and it starts over again.

my professional diagnosis..........your engine's buggered.

My guess is that its a combination of several things. If we could drive it we could probably tell you exactly what's happening.

High miles plus oil consumption plus knock-knock when its cold to me says cylinder wear which equals piston slap, Continued ping is from the oil consumption. Oil getting in the combustion space causes ping, and then its exaggerated by the fact that carbon build up from the oil burning makes the problem worse. The snick-snick is a lifter/follower problem.

Diagnosis (and this is official): consider yourself extremely lucky that your engine has lasted as long as it has... seriously. Many of those engines for chrysler/mitsubishi didn't make it to 100k and they smoked the whole way from 70k miles to their death. By 93 it wasn't as bad as in earlier years, but it still wasn't something I would consider a long-lived engine.

Prescription: drive it until it dies and then bury it. If all of those noises are happening at once, I take back what I said earlier... condemn it to death. Those are really signs of the end. Could be 10,000 miles, could be 20 miles, but I wouldn't rely on it as sole transportation anymore.

I don't think these sounds happen all at once, i'm sure its just the same sound that switchs into the next sound.

Now when i drive the car it feels the same, no lost power or hesitation.

I would record the sounds and upload them if i knew of a cheap way of doing that. I just have a tape recorded and a cell phone that records memos.

Is there some site that has the different sounds uploaded?

sounds almost never record very well

Out of all the sounds there has never been a metallic sound. I have heard this a fews times on cars driving by, sounds like a blacksmith striking his hammer, but slightly with a dull thud not so high pitched.

description sounds like a rod or piston. Both knocks can come and go with varying load, but should be able to force it to knock for testing. I take it your noise at times "cannot be made to happen" ?

Someone who looked at it thinks it might be a lifter arm or stuck valve, he thinks the sound is on top, but he is not a mechanic. I'm going to take of the front valve cover, so how do i check the lifter arms, or valves or do anything about it?

If i don't hear that sound when i take off the cover i guess thats my problem.

If i don't hear that sound when i take off the cover i guess thats my problem.

no, a cover is a cover. if it's the cover that's the problem then you'll hear a rattling sound. so the cover is not the issue

Someone who looked at it thinks it might be a lifter arm or stuck valve, he thinks the sound is on top, but he is not a mechanic.

why didn't you take it to a mechanic?

why didn't you take it to a mechanic?

because that would be sensible :p

yyyeeeeeesssssses.... and the next time i need an engineering report on the structural integrity of a project, I'll ask the bloke next door to tap on the walls and pretend to know what I'm talking about.

why didn't you take it to a mechanic?

Its not worth it for a p.o.s car. I'm sure they would just tell me its a rod anyways, its not worth getting fixed. If i knew somebody i would take it to them. So i just asked somebody who has worked on some engines.

I'm just going to sell or salvage this car. If the engine blows before i do so be it. I only paid about $300.00 for the car to begin with and had it for almost for 15 months.