Ok, I don't want to beat a dead horse but I am trying to get my vehicle running properly. You can see my other thread regarding engine noise. To make a long story short I have a sort of ticking sound that seems to come and go when you hit the gas pedal. I took it to the original dealer and got the "its normal" story. I then took it to another dealer and they thought that it was something that was coming loose in the exhaust system but they were unsure where. It sort of sounds like a baseball card in a bicycle wheel when it happens. They had tightened everything in the exhaust system and it didn't do it for 3 months. Now the noise is coming back. What can this noise be? We know it isn't the engine but what else? Skip plates coming loose? Heat shield cover on the catalatic converters? When it does it, it seems to only do it when I hit the gas firmly. Also when it happens there seems to be a lag in my truck when accelerating. Almost like there is something that is sort of acting like a wind sail and holding me back. Can anyone help? One day I can be driving and hit a bump and it is there, then hit another bump and it is gone again. I just want this to run right for once and for all. Please let me know what I should be asking the dealer to look at since they seem to be somewhat clueless. Should I just take this to an independent mechanic? Thanks all in advance.

If you ignore the fact that it comes and goes when you hit bumps, it sounds like you are pinging. Have you tried higher octane gas?

If it is something in the exhaust, it is probably an exhaust leak or crack in the exhaust manifold or where it connects to the exhaust system.

Hey Brian-
I think you replied to my other post too. Yeah, I have tried all octanes and makers or gas. I have tried Mobil, Exxon, Hess & BP just to name a few. Both with high and lower octanes. It continues to happen. Like I said before, it stopped doing it for 3 months after they fixed the catalatic converters and then pop, there it is again. Sometimes it seems to be louder when it is colder out and then quiter when the warmer weather comes. Quite upset that I have to go through so much trouble to get my truck working properly. If it is pinging, why don't I hear it on any other Runners? Is this a sporadic problem? Does it not happen to everyone?

If higher octane gas has no effect, then it is unlikely to be pinging. The further back you get from the engine, the less likely you are going to find the problem since the heating/cooling is much less intense. Put some dye penetrant oil on the exhaust manifold, let it sit for 30 min, then clean it off thoroughly and apply a developer. You may find a crack this way - most likely around bolt holes, flanges or sharp edges. Magnaflux would also work.

Another possibility: You can put some penetrating oil on the bolts holding the exhaust manifold to the head and the exhaust system on the other end. Loosen the bolts one at a time and then lubricate them with antiseize compound, if necessary tap the bolt holes, and then torque the bolts. You might find one or more of them were tight, but loose because of lack of lube or a dirty bolt hole.

The cat/ converter in my 97 blazer gave me similar symtoms when it came apart inside...when I kicked or rapped on it I could hear loose chunks inside...good luck

Ok Brian, I thank you for your reply. However, I have no idea what you are asking me to do. The only thing I know how to do is put gas and washer fluid in. LOL. I wish I knew what you were talking about as I don't think the dealer will take as much time to find out what is going on. It sounds as if it is coming almost directly from the engine but I don't think that is it because they fiddled with the exhaust system before and it went away so I basically wrote it off as not being that. I will have to see what the dealer will do about it. Most likely nothing and I will have a $33K piece of machinery that makes consant noise. I will definatley think twice about buying another if this is the kind of service they have in my area.

Sorry, I didn't catch the fact that you had a 2003 4Runner. The V6 version is known to have a ticking sound from the engine. I don't know if it has been fixed officially yet. Search this forum. We talked about this issue within the last 6 months.