Tapping Noise, Lifter Or Timing Chain?

[ridethelightning]

Hi All, I Have A '00 Eldo Esc With Aboiut 50k Miles. For The Past 5 K Miles Ive Heeard A Tapping Noise At Idle, Non Steady, And Worse When The Engine Is Hot. Sometimes When It Was Cold I Wouldnt Hear It. Now I Seem To Hear It All The Time Cold And Hot, And Still At Idle. I Work At Ford Motor Co. So I Took My Car In The Back, Had The Techs Licten To It With Thier Chassis Ears, And They Seem To Think The Noise Is Coming From The Timing Cover In Front, Or Possible The Serpintine Belt Tensioner Is A Little Loose, Or Even A Lifter Noise. I Seem To Hear The Noise From The Rear Bank, But They Seem To Think Its Coming From The Front Head. If Any One Has Had A Similar Problem Pleas Elet Me Know, Or If They Have Any Tips For Me. I Use 5w-30 Mobil One Full Syn. Always, With Ac/delco Filter. My Last Oil Change I Used 10w-40 To See If There Would Be Any Change In The Noise. The Noise Isnt Really That Loud. Im Not Sure What A Lifter Sounds Like If They Are Pumping Up. Thanks Guys!

[submariner409]

The first place to answer that question is in the archives or search function at the top of the page. Look for symptoms such as "carbon buildup", "carbon rap", "northstar carbon noise" , etc. Once you have an idea of one or more of the causes for "ticking" or "knocking" in a N*, try a couple of (engine warmed to highway cruise) good, hard WOT runs all the way through 1st and 2nd, let the engine unload, coast down to 20-25 mph, and do it again. (The crap that comes out of the exhaust the first time will scare you...) Look at your Manual and run the recommended oil for your engine. Witch hunts for the ultimate oil will cost you sleep and money. Mobil 1 or similar synthetic is fine. The N* is a highly tuned high RPM engine, and should be driven, carefully, as such (don't abuse it : run it.)(There are 3 single row roller chains in a N*. If you don't have plastic chips in your ((cut open and inspected)) oil filter, you're OK there...)

[Trashman]

my 99 is making the same noise sometimes,
thanks for the info

[ridethelightning]

Thanks for the replys guys. Unfortunately i have tried cleaning the engine out running it at WOT, a few times, with no luck. I just ran a little marvel mystery oil in there to see maybe if It is a lifter noise and it quiets down. I must say though based on my own personal experience, it sounds more like a spark plug wire arcing, but muuuuch louder. With the chassis ears on i can stil hear the noise coming from the left cylinder even when giving it some rpm's. Its hard to determine where exactly the noise is coming from though. when at idle its easiest to hear, and it still "off beat" not a steady tapping or rythmic. I have access to just about anything i need since i work at a dealership here, maybe i could decarbon the engine and see if that helps? I would just buy the cadillac extended warranty, but ive been quoted over $2000.00 for it haha. a little steep for me. any other thoughts would greatly be appreciated