99 4.0L SOHC fluttering noise at 2,700 rpm

[Humanuke]

Help! My new '99 Explorer 4.0L SOHC with less than 4000 miles on it makes an irritating "fluttering" or "light pinging" or "clicking or ticking" noise when accelerating when the rev's hit 2,700 rpm. The sound seems to go away as the rev's pass the 3,000 rpm mark. The sound is most noticeable when the engine is cold, thereby when I took it back to the dealer, by the time I drove there I could barely hear it myself. If I have to, I'll leave it there overnight, but I'd rather try to figure it out first with your help. One dealer suggested the injectors might be making the noise, but is this normal or is it repairable or adjustable?

 

[TPLYNCH]

Welcome to the site! Think you'll find answers to many questions here. As for your ticking, the only noise I know of that may be similar is associated with the timing chain tensioner problems. If you search this site, you'll find lots of info on this. Unfortunately, I think that noise is prevalent across the RPM spectrum, and not only in the rpm range you specified. The heat shield under the truck has also been known to come loose and cause a rattling/ticking noise too.

 

[eatonc]

SOHC Detonation

Humanuke

Hello,
I have had the same problem with my 98 Explorer 4x4 4.0 SOHC since new. When RPM's reach 2600 or above (even on light acceleration) the engine will ping loudly. It used to only happen for the first 15 minutes or until the vehicle was "warmed up". then it would go away and I would notice a power increase. Now it never goes away no matter how far I drive. The check engine light has never come on. Is there any way to change the engine timing or enhance it. Resetting the computer has no effect. I have tried different gas a still no change. I know it has been a while how di you ever make out?

[Edited by eatonc on 02-07-2001 at 07:19 PM]