I'm desperately hoping someone who recognizes the following "symptoms" or who works as a mechanic can help me out. I've posted on a lot of Hyundai discussions elsewhere, but with little success. I've been trying to get a couple issues fixed by two different Hyundai dealers now for four years, and with exception of the last issue that is listed below, all of the problems you are about to read about surfaced within the first 300 miles. Currently, I have less than one year left in Hyundai's five-year, 60K bumper-to-bumper warranty, so if I can't get anywhere with my warranty my only option is to pay for an independent shop to troubleshoot or file for lemon law (assuming it's not too late). Honestly, I just want my car fixed, so please jump in if you have any tips. 1. Engine rattles during acceleration (sort of a frog-in-the throat noise or perhaps a pinging like sound). It's especially noticeable when the roads are quiet, and grows more obvious in cooler, damp weather. The noise is most evident after the car has been sitting a couple hours, and fades out after about 5 to 15 minutes of driving. I seem to hear it best between 5-40 mph, after which the engine noise drowns it out. There are no dashboard lights illuminated to indicate a fault. Dealer has: replaced right motor mount and inspected valves/timing. I have: tried higher-octane gas with no improvement. Tried also a Lucas brand gas tank additive to clean engine. On the Internet: Heard that a faulty timing belt tensioner would cause a temporary sort of slack in the camshaft area that could reverberate with acceleration until the car reached operating temperature, but the dealer doesn't agree it is necessary to check the tensioner and wants to charge for the labor involved with checking the belts. 2. Valve clatter at startup that seems to take too long to settle down (about 4 minutes). The valve tapping isn't just when I do a cold start, but any time the car has been sitting as little as 1/2 hour. Dealer: Checked valve clearances. They also invited me to start up other cars on the lot that do the same thing, some even worse. But the problem isn't the noise alone but how long it seems to last. Took it to a second dealer whose tech said the valve lash was out of spec. When the corporate rep came on scene the next day, I was then told that no valve repair was required because the valves were in spec. Result: I am totally confused! I have: tried 10/40 oil, also tried Lucas oil additive at the last oil change. Not certain if this helped (concentration of additive was probably too low). I also took it to an independent shop, which verified my observation that the noise is valve train related. 3. When sitting at a stoplight, if I fail to hold my foot firmly to the brake peddle or ease up lightly, I hear a thumping noise from the right rear passenger side. It sounds like there is someone in my trunk banging his or her fist on the sheet metal to get out, and disappears after about 10 seconds. It sometimes starts up again when I pull into my driveway, put the car in park, take my foot of the brake and pull up the emergency brake. I then hear a series of thuds from the rear again. Except the noise has a sort of hollow ring to it. Dealer: Checked muffler, but otherwise could not duplicate despite multiple occasions where I asked them to attempt to do so. I have: Asked for the rear disk ABS brakes and hydraulics to be inspected. Not sure if anyone actually HAS inspected it. 4. After the right motor mount was replaced earlier this year, I began to hear what sounds like sheet metal buzzing whenever I engage the A/C and begin to back out of my driveway. When I hear the buzzing, I turn off the A/C button and it goes away. When I turn the A/C back on, I hear it again but only for a few seconds. If I let the car sit for a long while, the noise starts up again next time I engage the A/C. I also hear it sometimes when coasting at low speeds to a stop. Dealer has: Replicated the noise while turning the car in circles to the left, but thought it was a suspension issue and failed to fix it by tightening up suspension bolts. Can somebody tell me if there are any solutions before my warranty runs out next August? Also, if I take it to an independent mechanic and he fixes it whereas in four years Hyundai has been unable to fix it, would it be possible, legally speaking, to get Hyundai to reimburse my repair costs, since I have already gone to two dealers and even had their corporate tech out with no success eliminating items 1-3?