2005 Explorer 4.0L Valves chattering

[bowhunterga]

Hello all.....first time posting.

I have a 2005 Explorer with 198,000 miles on it. A few months back I was in a situation on an interstate where I had to accelerate as fast as possible to avoid being in an accident that likely would have taken my life. (Semi involved) I am not sure how high then engined rev'd but it was higher than I would normally allow. Afterwards I noticed a chattering in my valves starting at 2000 rpm and higher. It does not chatter (or at least I can't hear it) when accelerating rapidly, only when accelerating normally. I also do not hear it at cruising speeds, only when under light load.

I suspect that the timing chain tensioner is to blame but not sure. There is no loud noises like the chain hitting anything inside and the engine runs fine. The valve chatter has not gotten worse since then but it is annoying and just wondering what folks here think the cause may be?

Thanks in advance.

 

[2000StreetRod]

Rev limiter

The PCM limits the maximum engine speed to avoid damage. On my 2000 Sport the stock limit is 6250 rpm. The only way to exceed the limit is by downshifting or with a custom tune. However, driving at an engine speed well above normal driving may loosen sludge in the engine that can block oil passages. I suggest trying an engine flush just before an oil change.

If the noise persists it could be your primary (crankshaft to jackshaft) chain tensioner has failed. If you have AWD your balance shaft chain tensioner may have failed. If it is either of those you may find pieces in the oil pan.

 

[bowhunterga]

Thank you, may try the engine flush as I am due for an oil change, if it fixes it I will shocked. This sounds more like a timing issue to me we'll see. Any particular Engine flush you would recommend?

 

[2000StreetRod]

Gunk motor flush

I use Gunk motor flush and follow the directions on the bottle. You should never drive your vehicle with engine flush in it. Some flushes are so strong that bearing surface protection is greatly reduced.

 

[bowhunterga]

Thank you. Interestingly enough....today I had to fill up so I did something I never do.....I filled up with Premium.....all but eliminated the valve chatter.

 

[2000StreetRod]

Detonation?

Can you recognize the difference between valve chatter and detonation? Detonation typically occurs when the engine is under heavy load such as lugging the engine in high gear with the accelerator moderately depressed.

 

[bowhunterga]

I would cal it chatter. Is the same as when timing is off and you get that chatter at the point of acceleration but when you press the gass it goes away. Hope that makes sense.