Letters: Drive belt holds key to front-end noise

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Q: I own a 2000 Chevrolet S-10 with the four-cylinder engine. The problem is that there’s a cricketlike noise coming from the front end. The belt and belt tensioner have been replaced but the noise is still there.

I’m wondering if it could be a bad U-joint. How can I tell if the U-joint is bad? I don’t want to replace any more parts unless they will get rid of the noise. What do you think could be wrong? – George, West Chicago

A: If your truck has a worn U-joint, the noise would likely be coming from the middle or rear of the truck, not the front. Does the noise occur with the vehicle in motion, or does it happen when the engine is running and the vehicle is stationary?

If you only hear the noise when the vehicle is in motion, have the brakes and wheel bearings checked. If the noise is there when the vehicle is stationary, you’ll need to determine if it’s coming from the engine, the drive belt or one of the accessories driven by the belt.

This can be accomplished by running the engine with the drive belt removed, but don’t run the engine too long like this. If the noise is still there with the drive belt removed, your engine may have a worn timing chain. If the noise is there with the drive belt installed, but gone with the belt removed, you’ll need to check all of the accessories driven by the belt, and check the pulleys for proper alignment. There’s a special laser tool that’s excellent for checking pulley alignment.

Q: I own a 2008 Chrysler PT Cruiser. The car caught on fire some time ago and it has recently happened again. I’m being told that this is happening because my car doesn’t have a heat shield around the catalytic converter. What should I do about this? – Don, Chicago

A: Your car might be missing one or more heat shields. If so, new heat shields should be installed. Have the dealer or an exhaust shop inspect your vehicle. Also, have them scan the computer to make sure the engine is running properly. A poorly running engine can cause misfiring, which can cause the operating temperature of the catalytic converter to exceed normal temperatures and possibly lead to premature failure.

Q: I’m trying to find out if I have an interference or non-interference engine in my 2002 Ford Explorer. I’ve never had the timing belt replaced and the truck has 111,500 miles on it. I’m concerned that the timing belt might break soon, so I took it to the dealer. They told me not to worry about it. What do you think? – Mike, Chicago

A: I agree with the dealer, don’t worry. Your truck’s engine uses timing chains, not a timing belt. Timing chains generally last much longer than timing belts. In regard to the timing chains, there is no recommended service interval like there is for a timing belt. Just keep changing the engine oil at the recommended intervals and you should be fine.

Questions for Ira Siegel? Call the Auto Advisor Hotline at (708) 633-6839 or e-mail ira.siegel.is@gmail.com. Siegel is an automotive instructor and an automotive service excellence-certified master auto technician.