It's not from a Honda, it is actually from my parent's Astro van. It was having kind of a tapping, almost like a spark arcing out but not really, when you would start it up, just for like five seconds or so. Someone said change the PCV valve, so we did, and we had no problems. Until last night, we had recently gotten back from a 2hour trip. We had to go out someplace else, and when I started it up, the tapping came back and did not stop. It got quieter as the engine warmed up but kept going. My mother had told me that it was doing it on the way to work this morning also. I had looked it up and it seemed like the culprit was a bad lifter. Now, she just had to run to the grocery store, and when she started it up, there was no tapping whatsoever. No check engine light, everything is running good and smooth, no misfiring, nothing except this annoying tapping that comes and goes. Any ideas?

 

If it was a Honda I would have said it was just normal head noise but since it's an Astro, it's definitely your flux capacitor. Change that and drive it around about 88 miles an hour and it'll be good!

 

LOL, im serious about this though. In the morning, it was tapping. In the afternoon, it wasn't. Just started it up again to go somewhere, it tapped and slowly faded away. In about a minute, it was gone. What could it be?? I'm thinking I'm gonna rule out the lifters.

 

Piston slap. The chevy 6's are notorious for it. They use really short skirted pistons and until the piston warms up and expands in the hole you get a little side to side rock. It's not hurting anything...in fact the 5.3 vortecs do the same thing as the motors get over about 50k. Both my 07 tahoe and 02 silverado do it. Took it to the dealership and they said just let it idle a minute before you take off on a cold start and you wont even hear it.

 

ahh, i was going to post up springs..

some of the 6's have valve spring issues. my work van is a 6 and had a broken spring. dealer says it was on a recall years ago..but i could def see it being slap.. my van is quite noisy on start up as well.. i just let it idle a few minutes and its gone.

 

Like i said, some days it never does it, some days just for a while, some days it will do it the whole drive. The problem just started a month ago I never had this before not even the slightest bit.

 

check the oil level?

 

Does the starting of this tapping correspond with the changing of the seasons? What climate are you at? I ask because sometime people will have their oil changed in the summer at one of those "oil changer" places and they will recommend an oil that works great when the temperatures are in the 80's and then is too heavy of a weight come winter.
So for instance let's say they put in a 10w/40 last summer, in winter where I live the morning temperature is about 35 degrees, the oil will take on the ambient temperature and thus will take longer to circulate and lubricate the engine parts. When the same engine is started in the afternoon and the temperature is 65 degrees the oil will circulate much faster and thus the tapping noise will not occur. In the winter where I live I run a 5w/30.
Does that make sense? Hope that helps.