ancdmd

The TB was done six months ago during a large repair job to replace leaking timing control tubes (go figure BOTH of them happened to be leaking oil). The pinging was unaffected by this repair. I don't think I cant tell a difference between misfiring and detonation. There isn't any stumbling or loss-of-power feeling, which if I'm correct is what I would experience if it was misfiring. Power delivery is smooth but that annoying pinging noise comes and goes.

I have a history/tendency to throw parts at the car's issues, which I'm not proud of. As a result, a lot of components are not that old on this car. In spite of this I am surprised that I always seem to have nagging and persistent issues with the car. I'm always finding something that needs fixing, if it's not one thing it's another. I don't think my experience with the car is typical; my brother has an '01 with 250k miles on it and hasn't had half the issues I've had.

ancdmd

Replaced the upstream oxygen sensors today and BINGO the pinging is gone! The repair shop is 50 miles away and during the entire drive there the engine knocked every time I gave it some throttle. It's as if the oxygen sensors were very slow to react to the mixture change in the exhaust. On the drive home I stabbed the throttle and did all I could to get it to ping and heard virtually none. The car runs better and throttle response is a improved. Along with the temp sensor, the O2 sensors should definitely have been replaced at probably around the 100k mile mark. I got the Denso sensors for $90 total on eBay.

Lavrishevo

iTrader: (1)

That's great. I'm glad you got to the bottom of the problem.

Jabberwock

Thanks for taking the time to share the info on resolution to your pinging problem. It will likely help someone else going forward.

LSDoc

At 200K on my LS 430, I'm thinking this is one more thing to add to the list...
It just keeps growing. I'm trying to get 300K+ out of this ride!
Thanks!

Bocatrip

Hey Ancdmd. Glad you finally at this point have eliminated your nagging pinging issue. You have mentioned on an earlier post that you have a habit of throwing parts at problems to try and find a fix. Can I ask you this? What made you decide to change the precise oxygen sensor at this time that currently has resolved your problem or if I misunderstood, did you change all four? I did see it as a suggestion. Did you take the suggestion or did others have the same issue and had if fixed by replacing the oxygen sensors? Did you replace all 4 sensors? For me, I don't like replacing parts just because I think it might work. I like a diagnostic that proves what it most likely will be. I too have replaced an oxygen sensor in the past for the warning light but my car does ping on occasion. Just wanted to put my two cents in here. I truly wish you continued success in your fix, as I will consider it if my occasional pinging gets worse. I've read of many owners with extremely high mileage and original OS with no issues. . Hopefully your success will help others.. Thanks so much for your help...

Lavrishevo

iTrader: (1)

I don't want to answer for ancdmd, but post cat O2 sensors are only sniffers for the cat's so you don't remove them. The pre-cat or upstream O2 sensors and water temp sensor have the greatest effect on fuel to air ratio and would be the logical step chasing pinging issues.

ancdmd

After researching quite a bit on the internet I found that O2 sensors can and do wear out, apparently they develop a slow response to changes in the exhaust gas mixture. My pinging problem seemed to always occur under a change in the throttle.

I've done many things to keep the engine running well so I knew there wasn't much else that could cause the pinging. I use premium top tier gas all the time and I've run many cleaners through the fuel system so I knew it had to be clean. A new TB didn't help, so the timing wasn't the culprit either. I replaced the engine coolant temp sensor and noticed a change in the pinging pattern, so that convinced me that maybe the car was still getting skewed data to calculate the proper air/fuel ratio. Plus I had previously replaced the MAF so that was ruled out. To run a diagnostic on the O2 sensors would cost as much as just replacing them, so naturally I elected for new ones. I just replaced the upstream sensors since the downstream sensors don't affect the fuel management.

Bocatrip

Thanks for all the helpful advice. For the time being and with my car purring like a kitten, the original plugs are remaining where they were from the factory, and I will address the replacement when I have any issues and/or if I live that long! lol.

Bocatrip

PS. Timing belt decision with these miles? no brainer. Spark plugs? Nah... I'll wait another day or more....