PDA

View Full Version : ominous rattling noise under the hood



lifespeed
04-04-2014, 03:58 PM
I've been getting a slight rattling noise from under the hood when the engine revs up above 3500 RPM. Idlers and water pump are new, alternator, PS pump and and AC compressor are not. Timing set is original also. The engine runs OK, although it has been slightly rough at idle recently.

Any brilliant diagnostic suggestions? I'm going to try the stethoscope tonight and see if it will do it revving in neutral in the driveway. This does not sound good.

Edit: 112K miles on the car.

tbone
04-04-2014, 05:50 PM
Cats? Sound can travel.

fastblackmerc
04-05-2014, 05:54 AM
Does it happen all the time or when engine is hot or cold?

lifespeed
04-05-2014, 12:08 PM
I think it started pinging. I'll reset the PCM and see what it does. This happened a couple years ago, also. I wonder if my knock sensor works?

lifespeed
04-23-2014, 11:20 AM
Put it back to stock tune. Still makes the rattling noise. So I would think unlikely to be pinging. It is faint, but can be reproduced and identified, at least by someone who has driven the car for years and knows what it sounds like. This is a new noise, it did not make this sound for the first 112K miles.

You know what? It sounds a bit like a sewing machine. :(

martyo
04-23-2014, 11:28 AM
Are you just revving the car in park/neutral or are you talking about when you are in gear and driving?

lifespeed
04-23-2014, 02:57 PM
Are you just revving the car in park/neutral or are you talking about when you are in gear and driving?

It happens while driving. It seems to be reproducible at about 2200 RPMS accelerating gently, although I have heard it under other conditions also. If I accelerate hard I may hear it over a narrow RPM range, perhaps 3000 - 3500, but it is not real consistent.

It seems to require a certain load, or lack thereof, on the timing set to manifest. Of course I am assuming that is the problem. I have tried it with the air conditioner on and off. The belt, tensioner,idler and water pump are new. I will replace the alternator (for other reasons, need high output) in one week.

lifespeed
04-23-2014, 03:04 PM
Does it happen all the time or when engine is hot or cold?

I don't think it has to be completely warmed up to hear the noise. It certainly does it when hot. It also rattles at start up, but I think they all do. And I have used the Motorcraft anti-drainback filters for many years.

ctrlraven
04-23-2014, 03:20 PM
So it only makes the noise when you are actually moving or can you bring the rpms up in Park or Netural and reproduce the noise?

Does it rattle at start up after it has sat for a few hours, a day, several days?

Bluerauder
04-23-2014, 03:27 PM
So it only makes the noise when you are actually moving or can you bring the rpms up in Park or Netural and reproduce the noise?

Does it rattle at start up after it has sat for a few hours, a day, several days?

Timing chain ??? Here's another one that sounds like a sewing machine >>>>>>> http://www.mercurymarauder.net/forums/showthread.php?t=92948

lifespeed
04-28-2014, 10:49 AM
I'm debating hiring this done or doing it myself. There is the potential to save a lot of money. But I would have to buy the OTC cam tools also. It looks like a big job, but doable as long as I am careful.

Regardless of the vagaries of the rattle (sewing machine noise?) coming and going depending on engine speed and loading, the tremendous rattle at start up is sure to be timing chains from what I understand.

Any body here do this job themselves? Is it a reasonable DIY for somebody experienced working on cars?

ctrlraven
04-28-2014, 11:55 AM
I'm debating hiring this done or doing it myself. There is the potential to save a lot of money. But I would have to buy the OTC cam tools also. It looks like a big job, but doable as long as I am careful.

Regardless of the vagaries of the rattle (sewing machine noise?) coming and going depending on engine speed and loading, the tremendous rattle at start up is sure to be timing chains from what I understand.

Any body here do this job themselves? Is it a reasonable DIY for somebody experienced working on cars?
PM Seneca, he worked on another member's car and recently did mine, he could provide a lot more detail with tips on tackling it yourself.

I can get you the part numbers for gaskets, tensioners, chain arms and chain guides.

lifespeed
04-28-2014, 01:48 PM
Isn't the Ford Racing M-6004-A464 (http://www.summitracing.com/parts/fms-m-6004-a464) the way to go for parts? Iron hydraulic tensioners, aluminum-reinforced guides, steel gears, etc.

HBTMD
04-30-2014, 08:05 AM
I had pinging on mine until I replaced the fuel filter.

Runs perfectly now. :beer:

ctrlraven
04-30-2014, 09:35 AM
Isn't the Ford Racing M-6004-A464 (http://www.summitracing.com/parts/fms-m-6004-a464) the way to go for parts? Iron hydraulic tensioners, aluminum-reinforced guides, steel gears, etc.
Sure if you need to replace everything including the chains, secondary tensioners (hardly ever go bad) and steel gears. Replacing the extra stuff will only cost a whole lot more money.

I spent less than $200 in parts for the new metal tensioners, chain guides, chain arms and front timing cover gasket kit. My chains probably had some stretching to them but nothing bad and couldn't get the slack out of.

From AdvanceAutoParts Online store Enter promo code TRT30 to save 30%
Left Chain Arm
http://shop.advanceautoparts.com/p/s.a.-gear-chain-arm-left-7393/20687491-P

Right Chain Arm
http://shop.advanceautoparts.com/p/s.a.-gear-chain-arm-right-7394/20687436-P

Left Chain Guide
http://shop.advanceautoparts.com/p/s.a.-gear-chain-guide-right-7636/20280116-P

Right Chain Guide
http://shop.advanceautoparts.com/p/s.a.-gear-chain-guide-right-7636/20280116-P

Front Timing Cover Gasket Set
http://shop.advanceautoparts.com/p/felpro-timing-cover-gasket-set-tcs-45980/15780064-P


From RockAuto.com Enter promo code 88F24AB80255D3 to save 5%
These parts are listed under 2004>Ford>Mustang>4.6 SOHC>Engine>Timing Chain Tensioner
Left Tensioner
CLOYES Part # 95338

Right Tensioner
CLOYES Part # 95339

It ends up being cheaper to get the parts I listed from Advance rather than get everything from RockAuto. 30% off is hard to beat and if you spend more than $75 or $100 you get free shipping.

lifespeed
05-19-2014, 08:21 PM
Put a new Mechman alternator in (need high current to charge tent trailer deep cycle batteries while towing). I had been suspicious of the alternator One Way Clutch.

I don't hear the rattle as the engine runs up through the power band anymore. Haven't done a cold start yet but I'm pretty sure that rattle will still be there. But I was most concerned about the rattling at speed.

lifespeed
03-13-2015, 01:34 PM
The rattling appears to have returned. It is most noticeable as the engine winds up through the 3 - 5K RPM range. It happens under light loads also, I am pretty sure it is not detonation.

I am guessing either the timing chain or maybe the AC clutched pulley. All the idlers pulleys, alternator clutched pulley and water pump are new. I suppose I'll see if it can duplicated revving in neutral and then remove the serpentine belt to check.

lifespeed
06-02-2015, 08:43 PM
Got the car back from the Ford dealer today. New Ford Racing timing kit as well as hydraulic lash adjusters. Some lash adjuster surfaces showed a bit of grooving, could have just been the cam slapping around due to the bad tensioner.

The plastic primary hydraulic tensioner was indeed the problem. I could see the O-ring that was supposed to seal it to the block was compressed, damaged and otherwise did not look capable of doing the job. I guess this explains why oil age, viscosity, etc seemed to have an effect on the noise. And why it would mysteriously come and go. When the oil wasn't leaking past the tensioner too severely, it would tension. Otherwise it would slap when the chain dynamics were just right.

It is really to bad Ford screwed up on this one. The timing set appears to have the potential to approach the lifespan of the rest of the engine, but that stupid plastic hydraulic tensioner looks unlikely to do the job over time. Also explains how some people run to 200K without doing a timing tensioner job, and others don't.

Yet another design flaw. Good thing this car doesn't have many. ;)