2004 Nissan Murano Engine CHATTER ?

[pegasus71]

I have an 04 Murano with 115,000 miles and There is a noise under the front valve cover. It sounds like a typical hyd lifter but I beleive these use solid caps. This is troubling due to the inconsistency of the noise. It comes and goes. The noise will start sometimes in the am when cold, or on highway, or 1200 rpm, when you feather the gas to a certain rpm you can make it louder. Before I realized that these lifters are not hyd, I added Sea Foam and the noise actually went away for 2 days.(40-50 miles) Today the noise is back. Since new, I have used full synthetic oil , changed every 3k.
This is definately NOT a fuel damper.

This has me stumped. Any help would be appreciated.

[Warhammer]

Is it a whirring sound that is repetitive? If so, then my vote is one of your electric motor mounts.

[njjoe]

p71-

Each intake camshaft has a hydraulic timing adjuster at the front of the engine. Possibly one is failing? Timing chain, maybe? I can't think of anything else under the valve cover that would make the noise you describe.

-njjoe

[pegasus71]

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When the Tapping/Ticking noise is there, it will do it in park, I can rev the engine and it will get louder depending on the RPM's. My wife said the noise was loud yesterday on her way home, so today she took my car. I just started it in the garage and it is quiet.
I took the oil filler cap off and listened inside the valve cover with a hose to my ear and it is very loud in there. Damn noise sounds exactly like a friggin lifter. If these are solid then it can't the lifter cause it comes and goes. I would think if the lifter was loose or out of adjustment then it would be constant.
The oil has always been changed religiously by me ( I have owned since new) and the level is not low. I suppose it could be a chain/tensioner but it is Tapping/Ticking like a lifter, not a rattle, and It is too loud to be an Injector. The noise speeds up/slows down with the engine RPM's. I was thinking something hydraulic due to the fact that it is intermittent.------------------------------------------------------------------------------

[Monty2003]

Originally Posted by pegasus71

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When the Tapping/Ticking noise is there, it will do it in park, I can rev the engine and it will get louder depending on the RPM's. My wife said the noise was loud yesterday on her way home, so today she took my car. I just started it in the garage and it is quiet.
I took the oil filler cap off and listened inside the valve cover with a hose to my ear and it is very loud in there. Damn noise sounds exactly like a friggin lifter. If these are solid then it can't the lifter cause it comes and goes. I would think if the lifter was loose or out of adjustment then it would be constant.
The oil has always been changed religiously by me ( I have owned since new) and the level is not low. I suppose it could be a chain/tensioner but it is Tapping/Ticking like a lifter, not a rattle, and It is too loud to be an Injector. The noise speeds up/slows down with the engine RPM's. I was thinking something hydraulic due to the fact that it is intermittent.------------------------------------------------------------------------------

Do a search for fuel rail damper. If one of them goes bad it can sound like a bad lifter. The fix is pretty easy. The fuel rails are located right next to the valve covers so a faulty fuel rail damper can easily be mistaken for a valve ticking.

Brian

[pegasus71]

When the noise is evident, I put my hand around the dampers and don't feel anything. I should feel it right?

[Monty2003]

Originally Posted by pegasus71

When the noise is evident, I put my hand around the dampers and don't feel anything. I should feel it right?

A mechanics's stethoscope is very helpful in pinpointing the source of noises - essentially it is a probe attached to tubes attached to ear plugs. You can buy one at a good local auto parts store for $10-$15. Or - you can go ghetto and use a screwdriver (that's what I do).

Place the tip of a big/long screwdriver on the fuel rail and place the handle against the little flap of skin outside of your ear canal and push so that the skin flap folds into your ear and sound is transferred to your ear.

My most successful use of this technique was the diagnosis of a bad fuel injector - with the engine running I could hear the ticking of the injector solenoid on 3 injectors but not the 4th (4 banger acura)

IMPORTANT - it is dangerous to stick things (especially your head) near a running engine. Beware of belts and fans!


If it is a valve or a lifter at least you can get a sense for the bank and the cylinder. Could also be your belt tensioner - the stethoscope should tell you that right away BUT BE CAREFUL.

Brian

[turbizzy]

Sounds like maybe your timing chain might be slappin around due to a broken tensioner guide, i've seen quite a few do this on VQ35s. Search my threads, i've posted pics of what happens.

[pegasus71]

Izzy, There are no hyd lifters, correct? I can def rule them out. I will try to listen to the timing chain to see if that is what is making noise. What has me baffled is that this is intermittent. This thing sounds like a Mercedes Diesel , Ticking. Noise is definately in direct relationship with RPM's.
Thank You all for the replies.
Can the chain be done Engine -in-vehicle?

[pegasus71]

Does any one know anything about the Intake Timing Sensors?
Is this a possibility? Are they Hydraulic?
Will they make a "Ticking/Tapping noise ?

[turbizzy]

No they're not hydraulic. Yes you can pull the front cover off with the engine in the car but its work. Intake sensors don't make any noise nor do they move.

[Monty2003]

Originally Posted by pegasus71

Does any one know anything about the Intake Timing Sensors?
Is this a possibility? Are they Hydraulic?
Will they make a "Ticking/Tapping noise ?

The variable intake timing is controlled by engine oil pressure which rotates the intake (advance or retard). The oil pressure to the "vanes" that actually cause the relative rotation is contolled by a solenoid on each cylinder bank on the front of the engine. This solenoid pulses to control the oil pressure.

The solenoid on one bank is readily accessable if you remove the cover and if you use a stethoscope when the engine is making the noise you will know right away. The other is harder to get to.

What kind of oil are you using and has it been changed regulairly and recently? I ask because too thick of an oil in cold conditions might have something to do with it and dirty oil (really dirty) can plug up the passages and causing the variable intake timing not to work.



Brian

[Jonnybegood]

Trouble shooting:
1. Start car, rev a little, sounds fine.
2. Backup up out of drive way sounds fine.
3. Start up the road sounds fine.
4. About 1/8 mile up the road chattering/fluttering sound starts. Acceleration amplifies sound.
5. Put car in neutral. Chattering sound comes and goes while coasting.
6. Revving the engine in neutral while coasting amplifies chattering sound.
7. Engine in neutral at idle no sound, can hear rocker arms.
8. Revving the engine in neutral while stopped makes sound.
9. Sounds like a loose rocker arm.
10. The Sound goes away level after reaching full operating temperature.
11. Chatter rate does not seem increase with rpm.

OK I relieved this tells me that its not the power/drive train. Well may be just a little bit

Cause: Low oil, sound must have been coming from the oil pump as it was chocking for some oil to pump. Time flew by and wife driving a lot more, typically I change every 5 to 7 thousand miles. This time to my surprise 15 thousand was racked up. I hope my engines OK. It sounds and feels good. Chattering/fluttering sound is gone.

[TamynJoe]

My MO does a chattering sound even though it is full of synthetic oil My only option is to buy a mechanics stethoscope and checked yours in myself From what I've been reading and it all has been helpful I need to consider everything since there a lot of things written here lol which is a good thing. 1 thing that did help me was to open the oil filler cap on top of the valve cover and gave it a visual inspection oil was flowing on the cam freely as Willy so I can easily rule out any faults with the oil pump. thanks to all for your postings.

[marksky]

Originally Posted by Jonnybegood

Trouble shooting:
1. Start car, rev a little, sounds fine.
2. Backup up out of drive way sounds fine.
3. Start up the road sounds fine.
4. About 1/8 mile up the road chattering/fluttering sound starts. Acceleration amplifies sound.
5. Put car in neutral. Chattering sound comes and goes while coasting.
6. Revving the engine in neutral while coasting amplifies chattering sound.
7. Engine in neutral at idle no sound, can hear rocker arms.
8. Revving the engine in neutral while stopped makes sound.
9. Sounds like a loose rocker arm.
10. The Sound goes away level after reaching full operating temperature.
11. Chatter rate does not seem increase with rpm.

OK I relieved this tells me that its not the power/drive train. Well may be just a little bit

Cause: Low oil, sound must have been coming from the oil pump as it was chocking for some oil to pump. Time flew by and wife driving a lot more, typically I change every 5 to 7 thousand miles. This time to my surprise 15 thousand was racked up. I hope my engines OK. It sounds and feels good. Chattering/fluttering sound is gone.

I can't believe it, as I wasn't that low of oil, but putting in 1/2 a qrt fixed the that fluttering / chattering noise that just started....

Johnnybegood, given how articulate and though your answer below, I'd say you know your stuff. Thanks for this post. I'm having another issue.... I don't think it's plugs or coils (03 Murano w/ 150K miles) as I've changed about 4 of the 6 coils and the spark plugs in the past 20K miles, however, when I go to start the car I get a slight skip. What do you think is causing that? Thanks again for your post!