Mk2 2.0 D4 grinding/scraping noise

[xzirri]

Hi folks! I'm a new member here, although I've been reading quite a few threads here for a while now. However, this time around I was unable to find any posts on this issue.

I recently bought a 2004 2.0 VVT-i D4 with automatic transmission. The engine sounds and works fine but there seems to be some noise coming from the engine compartment. The best way to describe it is a metallic grinding/scraping sound. It's present when idle as well as when under load.

I don't have a stethoscope so I can't pinpoint the source of the noise but it seems to come from somewhere close to the exhaust manifold and alternator area.

I'm suspecting the manifold heat shield but I'm not sure, as it probably would be more of a rattle than a grinding/scraping noise?

Would truly appreciate all the help I can get!

Cheers, J!

[dew66]

I'm not familiar with this engine, but I have a suggestion - if it is possible can you remove the drive belt for the alternator to ascertain if that changes/ eliminates the sound. That test would show if an alternator bearing is the origin of the noise

Also, if that experiment doesn't help, tell us if the sound is rythmical and/or changes with engine speed. 

[xzirri]

1 hour ago, dew66 said:

I'm not familiar with this engine, but I have a suggestion - if it is possible can you remove the drive belt for the alternator to ascertain if that changes/ eliminates the sound. That test would show if an alternator bearing is the origin of the noise

Also, if that experiment doesn't help, tell us if the sound is rythmical and/or changes with engine speed. 

Thanks, will check it out!

The sound is not rhythmical, it varies slightly with the engine speed. I can upload a video clip later, as I am having a hard time describing the sound accurately

[Mike169]

Hi Johan, you might not have a stethoscope but you have an alternative tool. I have worked in many garages and what you can do if get a big long screwdriver, clean the plastic handle end if need be, if you have long hair get it out of the way, start you engine, put the handle of your screwdriver into your 'opened up' ear and press it on various places and as you get to the noise you will hear it in your ear drum. Mike. 

[xzirri]

Thanks Mike, will check it out when I get home. In the meantime, here is a short video clip with the noise in the background

IMG_5450.MOV

[Mike169]

Hi Johan, good video and sound by the way. Possible noises are timing chain if you have one, water pump, alternator, if cam belt driven then a pulley that spins with the timing belt, oh and I take it there is enough oil in the engine, lol. Mike.

[xzirri]

Hmm... That's a lot of things to check out! I guess the timing chain would be the culprit if the sound comes from within the engine (using the screwdriver trick you mentioned) but how can I check whether or not it's the water pump or the alternator? They are connected with the same serpentine belt  And yeah, got plenty of oil in the engine haha 

[Mike169]

Hi Johan, if you can manage to remove the serpentine belt and then start the engine that will eliminate many of the pulleys it goes round, a pump, alternator and so on. If the noise still exists with the belt off I suspect the noise is your timing chain which isn't good news...it may just be the adjuster needs changing but it's a lot of nuts and bolts to undo to repair it. You are welcome to come back to me, Mike.

[dew66]

Hi Johan,

I managed to extract just the audio from your video+sound clip and have looked at the frequency components (spectrum analysis) to see if there are any clues. Among the general clatter the strongest components seem to be at around 430 Hz, 660 Hz and 1060 Hz. Since these frequencies are much higher than the the rotational speed of the crankshaft (at idling, in the region of about 15 Hz or so) it seems most likely to me that the noise is not from the belt driven items but points more strongly to the valve gear and timing chain as suggested by MIke169 .

[Mike169]

Hi Johan, Dave and all.

Just to say I have amended/edited my reply, the one above dew66's as I used a wrong word, in error of course,

I must of had my wrong thinking cap on.

I used the word belt and not chain which may of coursed some confusion.

After reading Dave's reply I realised my mistake and have slightly changed my reply as the word I used 'belt' instead of 'chain' is an important error and for that I apologise.

After reading Dave's reply, excellent reply by the way Dave I only then realised my one word error and it was an important word to get wrong.

By the way Johan, how is your reply going, have you repaired it yet, if left there is a good chance the chain will break and basically you will have a scrap engine.

Regards, Mike169.

[xzirri]

Thanks for the answers, both of you! I haven't had time to disconnect the serpentine belt yet. Also, payday is a few weeks away so I'm letting the car sit until then. I hope it's just a ball bearing in one of the pulleys but if it's not I'd have to take a trip to Mr. T to fix it anyway...

I know the valve gear makes a lot of sound (to the point of making the car sound like a diesel) on the D4 engines, which is why I didn't notice the scraping noise until I'd bought the car.

I guess that belt is coming off this weekend, rather find the issue myself than paying Mr. T £ 200 for a simple search

Btw, is it possible to buy/replace the pulleys alone or do I have to switch out whole parts, like the water pump or alternator?

[Mike169]

hi Johan.

You do not need to buy an alternator, water pump etc if it is the chain rattling which we all suspect it is.

Take the belt off, start the engine and see if the noise has gone which we all doubt.

Anything that is driven by the serpentine belt that will stop revolving once the belt is removed means those items are ok if the noise is still there.

With the engine not running give these items, alternator etc a spin with your fingers to make sure they sound ok, no bearing faults.

Assuming you have a noisy chain you will need to change the chain and it's adjusting device including and other revolving pulleys it goes around including the 2 top cogs if you are feeling rich, and if you do not know 100% what you are doing then I suggest you do not attempt the job, you can easily do more damage than you thought possible, it's not called a timing chain for nothing, lol.

Mike.

[xzirri]

I honestly don't know what I should be hoping for... Timing chain replacement is quite expensive, I think it's gonna be at least £ 250 in parts, and then there's the labour costs... Starting to feel like this wasn't a good purchase... 

[xzirri]

Update: Mr. T wants £ 1000 for the parts, then £ 900 for the work if it's the timing chain!  How hard is it to change the chain by myself? What tools would I need? And what parts would I have to remove to do the job? I'm kinda hoping it's just a pulley atm

[Mike169]

Hi Johan, how experienced in mending cars may I ask as I get the feeling this could be a too big a repair for you.

Regards, Mike.

[xzirri]

I have replaced spark plugs, replaced and aligned headlamps, done a lot of electrical stuff, oil changes, replaced the windshield washer pump, brake discs and pads, springs, done some bodywork and the basic maintenance stuff. Nothing too serious. I've already paid £ 4800 for the car, not sure if I can afford another £ 2000

[Mike169]

Hi Johan. Before you worry too much as it is obvious you have some experience with car just take the serpentine belt off and see if the noise still exists, it is not 'timed' to the engine so it won't matter if you spin any pulleys and you need to spin the pulleys anyway to check your ancillaries are all ok, no noisy bearings etc. If anyone else reading this thread thinks i am giving wrong information please say so before Johan starts dismantling things, thank you. Mike.

[xzirri]

Thinking about taking off the serpentine belt today or tomorrow, will I get a check engine light if I run the engine without the belt?

[dew66]

My guess is that you'll very likely get some sort of  warning, but the engine only needs to be run for a minute or so.

If possible, can you make another recording of the noise without belt.

[xzirri]

Will do! However, seems like I won't be able to get the belt off today, my 19mm is too wide... It's incredibly tight between the wheel arch and the tensioner!

[alan333]

20 hours ago, xzirri said:

Thinking about taking off the serpentine belt today or tomorrow, will I get a check engine light if I run the engine without the belt?

It will show the Battery light, since the alternator won't be charging.  It shouldn't throw a fault light.  Don't run the engine for long with the belt off cos I'm pretty sure the coolant pump is also driven from the belt, so the car will overheat quickly.

edit... lever the engine over a bit (carefully) so you can fit your spanner/socket in.

[xzirri]

2 hours ago, alan333 said:

It will show the battery light, since the alternator won't be charging.  It shouldn't throw a fault light.  Don't run the engine for long with the belt off cos I'm pretty sure the coolant pump is also driven from the belt, so the car will overheat quickly.

edit... lever the engine over a bit (carefully) so you can fit your spanner/socket in.

Thanks, will give it a try! Otherwise, I'd have to do this tomorrow, as the hardware stores are closed today.

[Mike169]

Hi Johan, if the spanner is just too long then cut it in half so to speak, it's only a spanner and easily replaceable. Mike.

[xzirri]

6 minutes ago, Mike169 said:

Hi Johan, if the spanner is just too long then cut it in half so to speak, it's only a spanner and easily replaceable. Mike.

Not too long, it's too thick, as in it won't get between the bolt/engine and the wheel arch. Only tool I have at the moment in 19mm is a socket wrench, not a spanner, hence the width issue.

[Mike169]

Hi Johan, just curious, if you don't mind saying, what country are you in if it is ok for you to say so, just me being nosey, lol. Mike.