Well my car has been making a tapping noise...its really for the first second I start it up. I don't notice any performance loss. It sounds like someone is in the engine bay hitting my engine with something. at around 40 miles an hour it starts to get audible from inside the car again. Another thing I might ad is that is that the speed of the tapping is proportional to the rpm, not the speed of my car. or maybe an exhaust leak. I don't hear a whistle or anything. Any help?
Its possible that its an exhaust leak (ticking sound) do you have headers? It could be valvetrain noise as well (hard to tell from here) Put a long piece of rubber hose to your ear and put the other end to the engine while its making noise, in the area you suspect. This will help you locate the noise. Good luck!!!
I had that problem once. Found out it was the exhaust valve stem cap. Very anoying... Very easy fix if you have another cap. I ended up going to a wrecking yard & pulling them off of a 302. I took all 4 of them on one side. Needed spares in case another cap got a hole worn in it...
noise Have a buddy block off the exhaust with a piece of wood/cardboard while its running and see if the noise gets worse. Mechanics stethascope is cheap and works well for noises of this nature. Also, are you running a mechanical fuel pump? Listen to it carefully..as the arm gets worn or arm spring gets weak it will creat a tapping sound like a bad/sticking lifter.
it sorta sounds like you got an exahuast leak because you said it only does it when you start it and if i'm not mistaken metal expands slightly when it gets hot and so thats why it could go away. but thats weird that it would do it again around 40mph
Its after i start driving and it goes away in about 5-10 minutes of driving. Does not do it at idle that I can hear.
"Pinging" will only be audible (loud enough to hear it) under a part or full throttle load. Just starting the engine it is unlikely that you will hear any pinging. If it is a lash cap that is worn then it will start as an intermittent tap (at start-up and at certain speeds while driving it) and get worse over time. You could get lucky and find some lash caps at a wrecking yard but the best fix is to do what I did - get new valves that don't use the lash caps. It is expensive but I needed a valve job anyway so the additional cost of the valves was insignificant compared to the whole job.
it could also be a sticky lifter or slightly bent pushrod. check the caps like pauls said and check for the exhaust leaks. if that doesnt work, change your oil and filter and add a pint of marvel mystery oil to the oil. check your pushrods while checking the caps.
