2002 has tapping noise after cold start-up

[Alan G]

Hi. My 2002 S-10 with 56000 (mostly highway) miles on it has a rapping sound that is heard right after start-up , lasts for 30 - 120 seconds after which it then smooths out and purrs like a kitten! This is the case in the mornings after sitting all night. When the engine is not cold or when ambient temperatures are warmer, the noise is not heard but for a few seconds or not at all. Runs GREAT after warm-up. Could this be a noisy or bad lifter or possibly a slight exhaust leak?? How serious might the problem be since it does okay warm? Any help GREATLY appreciated. Thank you!

[movin2stereo]

Sounds like the oil is draining back and the sound is valve tappin.

[vtmecheng]

This sound is just what "movin2stereo" said. You have hydraulic valves and one is not pressurizing as fast as others, this tends to happen when cold out and the oil is thicker. Mine did this about a month ago and I found changing oils helped. Try Castrol Syntec Blend 5W30, made mine purr. Also, make sure to let it sit for a min or two before driving on cold mornings.

[sector95]

Originally Posted by Alan G

Hi. My 2002 S-10 with 56000 (mostly highway) miles on it has a rapping sound that is heard right after start-up , lasts for 30 - 120 seconds after which it then smooths out and purrs like a kitten! This is the case in the mornings after sitting all night. When the engine is not cold or when ambient temperatures are warmer, the noise is not heard but for a few seconds or not at all. Runs GREAT after warm-up. Could this be a noisy or bad lifter or possibly a slight exhaust leak?? How serious might the problem be since it does okay warm? Any help GREATLY appreciated. Thank you!

Gonna springboard off some of the good info already passed.....


Oil... what weight are you using? Most cars these days have a factory recommendation of 5W30. The "5" part of the equation means the oil will flow like a straight 5 weight oil when cold. Modern oil pumps and engine design are such that the lighter weight oil is needed to allow the flow for proper lubrication on a cold start. Using 10w30 is typically not needed and certainly not for wintertime use (and any oils stouter than this are usually *not* recommended).

Reference your owners manual for the recommended oil weights based on the tempurature range you expect to encounter.

BTW... how cold is cold? What are your overnight temps?

Oil Filter... oil filters have an anti-drainback valve as part of their design. Some filters have better ones than others. The valve helps to retain oil in the upper oil passages/galleries; an important function for long term (as in overnight) shut down of the engine. If you're using a FRAM filter or one of the no-name cheapies from the local Qwickie Lube, do yourself, and your engine, a favor and get a good oil filter. What's good? AC/Delco, NAPA Gold and Purolator all make very good filters with good anti-drainback valves. There's some good info on the web about filters and what's inside them. If you do allow the pimple-faced, semi-comatose neandrathals at the local "Kwik Loob" to change your oil then bring your own filter.... and prime it.... as in, fill it with oil before it is installed on your engine. Doing this will minimize the time your engine runs "dry" (zero oil pressure) while the oil pump first fills up the oil filter before building pressure and lubricating the rest of your engine. Tell them you want 5W30 oil (or at least check to make sure they stock it) otherwise you'll probably get 10w30.

If this were my truck, *I* would change the oil using 5W30 (dino or synth, whatever rolls your sox up or your wallet allows) and install an AC oil filter.... and see what happens.


Good luck and I hope this helps.


Happy New Year!


Mike

[StoneJoe]

Hmm sounds like a defective lifter or someone ran bad oil in it. I have the same problem with mine except it has gotton worse and now needs new lifters because of the one thats ticking. Mine actually callapsed the lifter one day when i went out to start it when it was real cold. I had to flush the engine with engine flush to get her un-stuck until i get new ones, You might try flushing yours it may or may not cure your problem depending on if its just dirty or it has a faulty lifter from running bad oil. I suggest running 10-30 pensoil petroleum (my first s-10 went 285,000 miles on pensoil and looked like new when i pulled the valvecovers off and didn't use oil) But there are skeptics who say pensoil has parafin wax in it,Well if it does it sure works good ;-) Also if it still ticks most mechanics don't know this but they do make longer pushrods(Comp Cams) and may cure that annoying tick for you without having to dig too deep.. The stockers are 7.187 inch and the Comp Cams Part #7808-12 are 7.195 inch they also have part #7608-12 which are 7.200 inch which should defiently cure any light ticking noise. Good luck hope this helped..

[brcidd]

I've used Resilone oil additive to cure a couple of "tickers"

[Leeann94astro]

Originally Posted by StoneJoe

Good luck hope this helped..

I hope that he got it fixed 4 years ago when he posted this, actually.

[StoneJoe]

Originally Posted by Leeann94astro

I hope that he got it fixed 4 years ago when he posted this, actually.

Lol i know, I didn't see any good responses so i figured i would put one there in case someone had same problem again..