Tapping sound coming from the engine?

[buugiewuugie]

When my car is sitting at idle, I can hear a tapping sound coming from the top of the engine. It goes away once i give it some gas. But as soon as it goes back down to idle it starts again. However it is louder when I first start it up but gets quieter the longer the car runs.. A friend of mine said he thinks its a valve. I think it sounds like a lifter. any way to know for sure?

 

[Old Mitsu Tech]

Probably the lifter. Before your next oil change, get a quart of Rislone and add to your engine oil per the instructions. Repeat if necessary. Lifters develop varnish over a period of time which reduces the travel of the valve inside of the lifter. This creates slack and leads to the tapping noise you have encountered.

If you can't find Rislone, Sea Foam works too.

Good Luck

 

[weith1111]

Add some Lucas Oil stabilizer. If the tapping lessens it's the lifters. If you are still on the 1g lifters and they have 100k on them or so, they are most likely all gunked up. Get the revised ones and they will tap no more! Search for "phantom knock" or "lifter tap" and there will be tons of threads on noisy lifters.

^^^bah, beat me.

 

[smail814]

hey it is probely the lifter my car does the same thing i added STP oil treatment and it helped it a little bit.

 

[sillyme]

can it be the valve lash? i have the same noise and someone told me i need to adjust the valves.

 

[mitsuclipsegsx]

Engine restore works good too.

 

[buugiewuugie]

I bet.. but I drive this car everyday. (or try to. seems like everyday something new is wrong with it.) So that might be a slight problem..


Thanks everyone for your replies.

 

[luv2rallye]

can it be the valve lash? i have the same noise and someone told me i need to adjust the valves.

Your someone doesn't know dsms since the valves are not adjustable (they have lash adjusters). BTW "Restorer" (at Walmart) works well for eliminating the tick tick tick (and it's blessed by Defiant even!).

 

[psychlow]

Your someone doesn't know dsms since the valves are not adjustable (they have lash adjusters).

Well, he's half right - gunked up hydraulic lash adjusters cause out-of-spec valve lash, which in turn causes the noise. You're right, of course, that you can't adjust them manually...

 

[sillyme]

thanks for the help. took the valve cover off today and saw that it can't be adjusted. trying pyroil engine flush soon.

 

[wret]

A separating crank pulley can make a tapping sound too. More of a rapping sound though.