I have a 2001 M6 completely stock. Never had a pinging issue until I took it out of winter storage a few weeks ago. I forgot to put gas stabilizer in and it sat for 5 months. It has been pinging since I took it out. I have run through two complete tanks of 93 octane and ran a bottle of octane booster through one tank. Still pings like an SOB at high RPM and seems to be getting worse. I just filled it with a tank of Sunoco 93 octane and dumped a can of SeaFoam in the tank. I ran about 10 miles or so.... still pings.

A have read alot about this in an effort to learn what to do and not bother anyone with a frequently discussed subject. However, I don't want to damage the motor and am at my wit's end on what to do or what is caausing this. I am new to Vettes, not a mechanic, but mechanically inclined with good directions. Thus, I am looking for some help.

1. What is causing this?
2. Much talk about the MAF What is it? How do I clean the MAF? Dumb question.... Where is it and what does it look like? Any photos?
3. Some talk about the temp sensor. Changing this sometimes fixes the problem. True? If so, where is it, what does it look like, and how do I change it? Any pictures?
4. Any other suggestions?

Thanks.

 

Sorry... Forgot... No Codes are showing up.

 

Maybe the injectors are a little gummed up or slightly clogged and you cant get enough fuel at WOT.
Might have to get the injectors cleaned if the seafoam or some techron wont get it done in a few tanks.

 

I have personally seen clogged cats cause a pinging problem.

 

Try the seafoam or techron and give it some time to work. Don't use the octane boosters, that stuff is garbage.

 

Car has 27k miles and did not ping before storing. How would the converters become clogged? Also, perhaps, I am only guessing it is ping? It sounds like BBs in a tin can at high RPM open throttle. Noise comes on more when it is warmed up completely.

In the interest of full disclosure, I i did miss a shift once last year (about 1,000 miles ago) from 3rd to 2nd instead of 4th. I never heard any strange noises at idle or otherwise so I don't think I did any damage. Car runs like a top.

 

My car ran fine, put a cam in it and when I started it, it wouldn't run. I messed with it for days and finally blew a converter out the tail pipe. I can't say why it happened. I just know it was fine the last time I drove it. Not saying that is the problem. Just saying maybe it's something else causing it. I use HP tuners to tune and it will log my runs showing any knock retard. You might end up needing to take it to a tuner for logging and diagnosis.

 

Perhaps what I'm hearing is not pinging or knock? I had cars that pinged back in the early 80's. This sounds a bit different but this is an aluminum block vs. iron. This sound is a bit higher pitched than the old days. It's only at high RPM (4,500+) when I have it to the floor (or nearly) that I hear this rattling sound.... It could almost be described as sounding like a haphazard electrical spark as well. I think its pinging but want a gut check from those that have heard it before.... It's really a high pitched rattling sound. Thanks to all.

 

it could be H pipe rattle.....

 

Thanks Defender C5. Are you still in Iraq? God Bless! Also, I am planning on cleaning the top end through the PCV with SeaFoam.... Better than through the gas tank? Thanks.

 

It's pinging. My 2001 LS1 WS6 T/A did it. I always thought it was due to oil in the intake --> combustion chamber. Did it on hot days on 93 octane.

 

Bingo. Often overlooked! GM had a problem with cats, at least up until 2002. One of mine was failing and was not throwing any codes. Had them both replaced under warranty. This was my 2002 LS1.

My 1999 C5 has at least one failing cat. GM cats are garbage.

 

But my '99 FRC is doing the exact same thing. Pinging at high rpm under full or close to full throttle...

OP, did you fix the problem???

We don't test here in FL, is there any harm to just cutting them out???

 

1 bottle of seafoam into the tank... Works like magic