(sorry for the long first post, but want to give out as much info as I can)
I am new here, and have a question that I have never had an answer too. I have 2006 Tacoma Prerunner 4 cyc, 2 WD, 5 Speed Manuel trans, extended cab with about 67,000 +/- miles. (mouthfull there). Here is my question. I have noticed that when I start my truck in the morning (regardless if it is cold outside, or warm) I can hear a rattling noise under my hood. Sounds like like a spring is coming unraveled. It sounds like it is on the driver side, kind of behind the steering wheel. It only happens when the engine is cold I have noticed. I have taken it to the dealership to see if they can duplicate the problem, and of course with all dealerships they say they can not duplicate it or so they say. anyone else here had the same issue, or at least able to pin point where it is coming from? In addition I don't use my A/C at all, and dont hear anything from the cabin air filter either, so I dont think it has to do with that at all.
I am not a mechanic or anything. So, sorry if I dont explain it right.
I have never heard this sound before in any vehicle that I have owned. It only happens when I start the truck, and it is sitting at idle after the initial warm up. It will make the noise. Stop for a sec, then make it agin. I almost want to say it is the big fan that is on the engine block. The best way I can discribe it. For those of you who have ever had or used a badge holder that retracks. You know that when the spring inside breaks, it makes a very distinct unraveling noise. That is the kind of noise I am hearing. I have started the truck, hopped out, and listend to the engine from under the hood, and so has a friend of mine, we can't really hear it. However when I get in the cab you can hear it clear as day.
I also got under the truck to listen to see if the starter is the culprit, and yeeaahh no noise from there. I did try to record the engine with my phone, but the file is not supported. I can try again, and see what happens... After I thought about this for a while, I remeber that the mystery noise does seem to much worse durning the winter, and not as bad during the summer. Also when I was under the truck, I could hear the noise a little bit better from that angle, and seemed like it was coming from the front more. I did have my water pump replaced by the dealership as well last year, cause there was a leak. However that was when i took it in the first time, cause of the sound. I have checked all wires, shrouds/covers, and dont see anything that is loose, or out of place.
I plan on keeping the truck for a while, and to be honest i dont really know much about engines in detail. I understand the basic's ok, but not the detail. So, any help, and suggestions is much appreciated. I am checking things off as I go. Please help....