I think its probably a lifter. The car has sat the majority of the last two years. I bought it a month ago and my wife has been driving it daily. Now today we took off and we hear a tapping noise, quite loud at first. It is definetly from the engine, gets faster and slower depending on rpms. Then once the car heated up good it went away and now I can't make it start doing it again . Do these have hydraulic lifters?

 

Yes, hydraulic, flat-tappet cam and lifters. After sitting for two years, varnish on the plunger bodies of the lifters would not be a surprise. Running the engine and changing to clean oil may have eliminated the problem. Since it sat for two years, you might want to consider changing the rest of the suspect fluids as well, like transmission oil, axle oil, brake fluid, power steering oil, and staying on top of shorter interval engine oil and filter changes for a while.

 

Thank you Vader, I did the oil and rear end and tranny flush before we even started driving it, what concerns me is that we have put probably one thousand miles on it before it started making the noise. I'll try changing the oil again though before ripping it apart. Do you recommend any different viscosity?