[Gumby_]

Hi all, I posted this in the jetta/golf mk2 section but it hasn't gotten any traction. Given the topic, I perhaps should have posted it here first.

Not quite sure how to describe this so that people can understand what I mean, but I figure those experienced enough will know what I am talking about. I have a 92 Digi II 8v Jetta and I get what I can only describe as a slight metal on metal rattle when I accelerate hard or if I am pushing the engine hard (ie: pedal to the metal going up a large hill or even accelerating hard from a stop). The noise is louder and faster as the RPMs increase but again, only if the engine is pushing (pulling?) hard. I can cruise along at a high RPM and not hear the noise, again, it only happens when under loads like hard accelerating or the car is going up a relatively steep incline.

Im not sure I can explain it any better than that but if anyone has any ideas please let me know. Oil (20w 50) is topped up. I may need a new oil pump soon as I had been getting the oil light/buzzer go off sometimes when the RPMs were falling and hit around 2100 RPM. A quick rev of the engine would make it go away. I changed the oil from 10w 40 to 20w 50 after reading some forum posts and since then the light/buzzer has only went off once. The oil light issue perhaps isnt (perhaps is) relevant to this question but I thought I'd include it in case it offered any clues to the problem.

Thanks all for your responses

 

[ziddey]

pinging.

is it hot outside? are you using low octane gas? is your knock sensor working? ignition timing set properly? ignition components in good condition? carbon buildup in the intake, combustion chambers? o2 sensor working properly? fuel filter clogged? fuel injectors spraying well?

chevron techron in the fuel tank.
seafoam the intake.
new bosch copper spark plugs.

 

[Diamondstar693]

Does it sound something like this? Listen to rattle sound here

 

[Diamondstar693]

Does it sound something like this? Listen to rattle sound here

PROBLEM SOLVED thanks to LIQUI MOLY CERATEC additive… Awesome stuff!

 

[Butcher]

What? First you post a clip that sounds like you are drinking beers on the beach and then you say some chemical fixed your noise problem.

 

[Diamondstar693]

What? First you post a clip that sounds like you are drinking beers on the beach and then you say some chemical fixed your noise problem.

If that’s what it sounds like when you’re drinking beers on the beach you’re doing something way wrong…and yes, the ceramic additive did the trick, engine is running smoother then ever, no more “diesel engine-like” rattle.

 

[Butcher]

Hey, maybe it's my computer but I hear nothing but waves on the beach. It would not be the first time someone downloads an audio clip and because of the compression factor, the 'real' sound is missing. I've had plenty of clients send me clips and I heard nothing. When we compare the sound, you can clearly hear the original recording but nothing after the download to me.

I'm not a fan of chemicals. Except for something that prevents differentials/torque converters from shuddering, it's all snake oil to me. The end result, if you think it's fixed, that's all that matters. It should not matter to you what I think. You are the one that is happy.

 

[Diamondstar693]

Hey, maybe it's my computer but I hear nothing but waves on the beach. It would not be the first time someone downloads an audio clip and because of the compression factor, the 'real' sound is missing. I've had plenty of clients send me clips and I heard nothing. When we compare the sound, you can clearly hear the original recording but nothing after the download to me.

I'm not a fan of chemicals. Except for something that prevents differentials/torque converters from shuddering, it's all snake oil to me. The end result, if you think it's fixed, that's all that matters. It should not matter to you what I think. You are the one that is happy.

This is the original audio: 1.8L TFSI CJEB Rattle Sound.m4a

The actual “diesel engine-like rattle” can be clearly heard on the audio at 4sec, 8sec, 10sec, 18sec, 26sec, 37sec & 38sec just as the accelerator pedal is pushed down each time… starting from a stopped position at about 1200rpms. However sometimes the rattle would also occur, with a longer duration in time (about 3-4secs long) at about 2000rpms when moving at about 25km/h and pushing down the gas pedal to accelerate.

My mechanic thinks that the distribution/timing chain has possibly stretched a little due to the repeated heat expansion & contraction and the slight slack is causing the rattling as the chain vibrates against the tensioner (2014 1.8l TFSI 3rd Gen EA888 motor CJEB config with 30,000 km in an Audi A4).

Apart from changing the distribution kit (maintenance schedule recommends a distribution/timing chain change at 120,000km) my mechanic actually suggested an oil thickener to temporarily reduce the vibration & rattle but I had already added the Liqui Moly Ceratec ceramic additive after an engine flush & oil change that morning (on a Friday).

He told me that he can get the oil thickener into the shop the following week but the rattle stopped over the weekend. The only time it kinda happened again was going up a 25 degree incline on a corrugated-grip-like surface at 1200rpms starting from a stopped position, but on that occasion the rattle wasn’t as pronounced as before.

I really dunno but my best guess is that the ceramic additive reduced the friction of the chain against the tensioner enough to stop the vibration & rattle, unless under heavier load a low rpm when getting underway (like on the corrugated incline) but that’s just pure speculation on my part. Any thoughts on your part?

 

[Butcher]

I know you think I'm trolling you but I swear, there is no audio noise that even makes you think it's an engine. Try finding a different computer and download the clip like the rest of us. I don't think you will hear anything and agree, it's just waves on the beach.

Maybe someone else could chime in and support me or confirm I am a troll.

I believe I mentioned, I'm not a fan of chemicals. If metal wears, then no chemical will put all the metal back. If something is gummed up, I can see that maybe a chemical can help but I just don't see it happening in my life. It's a lot like glue. Glue does work, but the only glue that works for me is super glue and it's only good on my fingers.

As I tell all my clients, if you got noises, there is something wrong and to determine what is wrong, it's got to be opened up. Many times, I've seen/heard the problem before so I can say with confidence what is wrong.

The only thing I can support is that trying a chemical to fix a problem is cheaper/easier than spending $1000's to fix it right. Thousands many people really do not want to spend. To throw $40 on snake oil, knowing it may not work, is no worst than going to the casino and hoping for a big pay out. It can happen, but probably not.

 

[Diamondstar693]

I know you think I'm trolling you but I swear, there is no audio noise that even makes you think it's an engine. Try finding a different computer and download the clip like the rest of us. I don't think you will hear anything and agree, it's just waves on the beach.

Maybe someone else could chime in and support me or confirm I am a troll.

I believe I mentioned, I'm not a fan of chemicals. If metal wears, then no chemical will put all the metal back. If something is gummed up, I can see that maybe a chemical can help but I just don't see it happening in my life. It's a lot like glue. Glue does work, but the only glue that works for me is super glue and it's only good on my fingers.

As I tell all my clients, if you got noises, there is something wrong and to determine what is wrong, it's got to be opened up. Many times, I've seen/heard the problem before so I can say with confidence what is wrong.

The only thing I can support is that trying a chemical to fix a problem is cheaper/easier than spending $1000's to fix it right. Thousands many people really do not want to spend. To throw $40 on snake oil, knowing it may not work, is no worst than going to the casino and hoping for a big pay out. It can happen, but probably not.

I guess you must have a crappy sound output on your computer. I’ve listened to the audio on my desktop, laptop & phone and can make out the revving of the engine with the rattle on each system without any difficulty.

Your take on the workings of a motor are quite odd in my opinion. Without the right chemicals an engine wouldn’t even run, so of course additives can have an impact & effect on an engine’s performance, sound & behaviour.

On the other side of the coin, add gasoline to the oil & see what sorts of noises & sputters the engine will produce as the cylinder walls score & the bearings fail. Gasoline in the oil surely won’t add metal back but it would definitely take metal away. A significant increase or reduction of friction in an engine will certainly change its sound, performance & behaviour.

 

[Butcher]

It is certainly possible that my laptop sucks. Although it is not that old I'm willing to acknowledge that is the problem. Hell, it might just be my hearing too. My eyes suck, but I can still hear my wife complain.

I certain was misunderstood. Yes, you need fluids for your engine to survive. I think we all agree with that. What I am saying is, I have a tough time believing that if a metal object is worn that a special additive will fix that. Something is not right if there is an abnormal noise.

I worked at a Mercedes and BMW dealership for 30 years. At no time did the factory recommend any chemicals. Except for Techtron in the 80's. If you follow their guidelines, you'll be fine. Yes, I do understand the factories are not perfect and they do make mistakes. God knows I've fixed many of their screw ups in 30 years but you're better off to follow them than to go out on your own.

I own a shop. I stand by all my repairs. I would not stand by some chemical that says it will reduce noises, oil consumption, etc. As I mentioned, one that that I have seen that does work is additives to prevent a limited diffs, torque converters, and transfer cases from shuddering. I do believe it is the additive package that allows those clutches to slide and some of them cause it to shudder. Putting the right additive will fix that. If those clutches are worn out, then no amount of additive can fix that.

But hey, I'm glad we can have a discussion without throwing too many rocks. In the end, if it fixes your complaint, who am I to say it is wrong? Heck, it may help with someone else's problem and maybe [like the shuddering problem I mentioned] I can be a believer too.

 

[Diamondstar693]

It is certainly possible that my laptop sucks. Although it is not that old I'm willing to acknowledge that is the problem. Hell, it might just be my hearing too. My eyes suck, but I can still hear my wife complain.

I certain was misunderstood. Yes, you need fluids for your engine to survive. I think we all agree with that. What I am saying is, I have a tough time believing that if a metal object is worn that a special additive will fix that. Something is not right if there is an abnormal noise.

I worked at a Mercedes and BMW dealership for 30 years. At no time did the factory recommend any chemicals. Except for Techtron in the 80's. If you follow their guidelines, you'll be fine. Yes, I do understand the factories are not perfect and they do make mistakes. God knows I've fixed many of their screw ups in 30 years but you're better off to follow them than to go out on your own.

I own a shop. I stand by all my repairs. I would not stand by some chemical that says it will reduce noises, oil consumption, etc. As I mentioned, one that that I have seen that does work is additives to prevent a limited diffs, torque converters, and transfer cases from shuddering. I do believe it is the additive package that allows those clutches to slide and some of them cause it to shudder. Putting the right additive will fix that. If those clutches are worn out, then no amount of additive can fix that.

But hey, I'm glad we can have a discussion without throwing too many rocks. In the end, if it fixes your complaint, who am I to say it is wrong? Heck, it may help with someone else's problem and maybe [like the shuddering problem I mentioned] I can be a believer too.

Well, I was certainly surprised when the VW motor started making that “diesel-engine-like” rattling sound at less than 30,000km. One so-called “Audi expert” mechanic who claimed to have worked with VW/Audi & Porsche for over 15 years and now owns his own shop did “open ‘er up” and decided to change the Cam Bridge/Bracket after pondering things for 3 weeks (with my car in his shop) since the part had underwent some modifications (which part hasn’t since 2014).

It was a complete & utter waste of time & money. I ended up with the same rattle seemingly worsening, a perfectly fine extra Cam Bridge/Bracket in my hand and a few hundred dollars less in my pocket.

In all fairness to Liqui Moly, they do have independently conducted tests showing that their Ceratec product does reduce friction in the engine by filling in metal scuffing & lessening metal to metal contact by applying nano-sized ceramic particles: Dual protection with Cera Tec

I had nothing to lose & in all honesty was actually pretty shocked and pleasantly surprised when the rattling stopped.

 

[Butcher]

And that is all that matters. Reading comments from some internet butcher cannot effect what happened.

As a mechanic, it is extremely hard to diagnose engine noises when it is disassembled. You should try it sometime. Just expect people to comeback to you and say you stole money from them.

BTW, there are plenty of parts that have not been updated. Contrary to popular believe, the factory does do it right the first time, many times. Fortunately that they look to better the product as the years go by.

Usually when I get something like this, I advise the client by email on what may or may not happen. If it is hours/days to replace this suspected part, I may just bow out of the job. Why? Because I could careless what people think about me but I will never have someone say I ripped them off.

If it is a job that only takes an hour or so, I will swap out the part and if it does not work, I will charge the client for the part only. That is my line in the sand. I will not buy parts for your car. If it is a cheap part and quick labor, I will just eat the entire job and politely say 'I do not know'.

All of this to prevent people who seem to know it all to not say bad things about me.

It is weird that people expect mechanics to be perfect with everything they do. I do not know any other industry that is held at such a high expectation. When was the last time someone went to the dentist or doctor only to leave with the same problem? We are human and none of us know everything. We do not have endless amount of time and money to fix your car. We did not design cars, just fix what was already made.

On the other side of the coin, I work in an industry that are a bunch of idiots. No, not all of us are but there are enough of them that really screw it up for the good ones. We try our best to take care of the problems that are difficult to resolve and when we fail, we get trashed like the others. Why would any good mechanic take on a problem job when there is so many better jobs that pay more, less liability, and less stress?

I participate on a forum that is only professional mechanics that ask for help. I swear, the questions that are asked is a lot like a bunch of DIY'ers. Not my fault, I was raised that if you have to ask for help, you are not trying hard enough. If you say you don't know, you did not research enough. Tough as a kid, but damn, they were right.

I have none of these problems with my clients. If I do, they are no longer my client. Most of my clients feel I do not charge enough. Most of my clients I have built up such a strong relationship. I am more fortunate to have good clients than my clients having a good mechanic.