2004 knocks at startup

My 2004 knocks or pings during initial startup if the engine is already warm. The knocking (like a gargling from the engine) subsides very quickly when the engine actually starts running. It is ignition knock and not bearing or lubrication knock. Anyone experience this? I know they claim this vehicle will run on any type of reformulated or ethanol gasoline. Could that be related? I know any type of knocking is not good for an engine. My 1997 Tahoe had the entire engine replaced under warranty because of an oil related knocking when cold. I'm a little paranoid.

Go to piston slap.com to learn more about your problem. Chevy is a big disappointment in my opinion, I have always been a chevy guy but at 9000 miles mine started knocking at start up and they say its normal. You don't have to be a frekin genius to know taht any metal to metal sound is not good especially after spending 40k

Will using a engine oil additive like Lukas help? My Tahoe has 180,000 km on it. I have used synthetic motor oil since I got it with 100,000km. I started using synthetic because I noticed the knock on cold starts. How about using a heavyer weight oil 10w30 instead of 5w30? Has GM actually done anything to resolve this problem? My truck is out of warranty.
Thanks

my 95 has done this exact thing for months, i just use hyper lube at every oil change, seems to keep the noise down slightly more than it used to. ive had this same problem with an 03 cube van. two years it did this, and no major damage happened. should be fine i spose.

I can tell you now, you better get a "new engine" real fast. 1996, I bought a new '96 Chev. Tahoe with the 5.7 liter SFI engine. I had it about 2 months (about 1,225 miles on it) when the "chatter/knock" started at startup, and sometimes would continue for a couple minutes. I taken it back to the dealer...who said..."don't worry it's only a chevrolet, and they all make the same noise"... just forget about it, and bring it back when something serious is wrong. Well, I drove it another thousand or so miles, and when back to the dealer for the same reason. This time I went to the "big guy", one who is over the shop manager. He wouldn't spend the time with me, claiming I was just to concerned about a "little" engine chatter.
So, I made a trip down the hall to the owner's office, who did the same thing...did not take me serious. So, I said a few words like... "if you don't do something about the engine in my new Tahoe, I'm taking a baseball bat, and I will see how many plate glass windows you have to replace in this showroom". His eyes got real big and made a phone call to the "big guy boss", who ask me to bring the Tahoe around to the back and they would check the "chatter/knock" more throughly... I watch from about 6 inches away, and heard the mechanic that had this large laptop type machines with test probes, tell the "big guy"...this engine has to be replaced.

The dealer gave me a new vehicle to use, and three days later, I had a "complete" new engine installed....no charges...

Today, June 9, 2008 I still own the '96 Tahoe with 112,000 miles. Never had another problem

My 2004 knocks or pings during initial startup if the engine is already warm. The knocking (like a gargling from the engine) subsides very quickly when the engine actually starts running. It is ignition knock and not bearing or lubrication knock. Anyone experience this? I know they claim this vehicle will run on any type of reformulated or ethanol gasoline. Could that be related? I know any type of knocking is not good for an engine. My 1997 Tahoe had the entire engine replaced under warranty because of an oil related knocking when cold. I'm a little paranoid.
I have had some success with using a synthetic engine oil (Mobil 1) to reduce or eliminate the noise. Sometimes the noise is from carbon build up. I always recommended to customers that they use a Top Tier Gas to keep carbon and fuel system deposits from being a problem.

like i said ive been driving mine for months that way, it only knocks for about 2 secs when i start it, definitely not minutes, id be a little worried then. ive put over 10k on it now. like a rock haha.

almost forgot, i only use plus or better grade fuel too, never have run cheap gas either, only shell or chevron.

almost forgot, i only use plus or better grade fuel too, never have run cheap gas either, only shell or chevron.
87 octane is all you need. I don't think you understand Top Tier Gas so here is the link. Shell and Chevron do sell Top Tier. http://toptiergas.com/

chevron and shell were both on the top tier gas list, what do you mean? i just mean i dont go to arco, worst gas EVER! every car ive ever put arco gas in, wouldnt run right without it after using it

chevron and shell were both on the top tier gas list, what do you mean? i just mean i dont go to arco, worst gas EVER! every car ive ever put arco gas in, wouldnt run right without it after using it
Some people think that Top Tier Gas is only the higher octane grades which is what you mentioned using. Top Tier Gas includes 87 octane also. Your vehicle needs only 87 octane and you're wasting your money buying higher octane. If your engine has the cold start piston knock it will run forever and not fail because of that condition.

no i know what u meant by top tier, i just choose higher octane as well though, because it has been shown to leave less deposits behind, less unburned fuel (more efficient) and im driving a tahoe, if i was worried bout gas money id be driving a hyundai little 4 banger haha, but ya htanks anyway for the info

My 2004 knocks or pings during initial startup if the engine is already warm. The knocking (like a gargling from the engine) subsides very quickly when the engine actually starts running. It is ignition knock and not bearing or lubrication knock. Anyone experience this? I know they claim this vehicle will run on any type of reformulated or ethanol gasoline. Could that be related? I know any type of knocking is not good for an engine. My 1997 Tahoe had the entire engine replaced under warranty because of an oil related knocking when cold. I'm a little paranoid.


this posting is 4 years old !!!!!