Q & A #52 With The Auto Specialist
Q & A #52 With The Auto Specialist
Thanks for joining me for today’s segment of the Auto Specialist. Earlier, I read that Toyota is making plans to double the global output of hybrid vehicles to over 1 million by 2011. Toyota and Honda continue to battle for the frontrunner position on low-emissions cars. To say the least, it will be interesting to see how this battle plays out. Plus, given the components that are installed in today’s vehicles to lower emissions (i.e. catalytic converters, oxygen sensors, etc.), it will be interesting to see how those evolve.
In the last segment, we helped three readers with their car problems. Tom was having an issue with his alternator; Brian was dealing with a coolant leak into his engine’s cylinders; and Dawn was coping with the bad news following her car’s spark knock. Today, we have a good batch of three new questions.
Let’s get started.
Question: I have a 2002 Ford Explorer with about 103,000 miles on it. Last week, I was driving home from work and my timing belt broke. It didn’t just slip a notch. It actually snapped. Unfortunately, when it broke, it did some damage to my engine. My mechanic said a couple of pistons are broken and the intake and exhaust valves are bent.
The worst thing about it is that my mechanic had told me to replace the belt a couple of years ago. I didn’t take his suggestion seriously because I figured he was just trying to pad his bill. Can you explain why the belt caused so much damage?
Answer: Thanks for writing, David. Your timing belt goes around the crankshaft, camshaft, and water pump, and helps to control the timing of the intake and exhaust valves. If everything is working properly, the valves will open and close in perfect sync with each piston’s rising and falling within the individual cylinders. When the belt breaks, everything goes wrong.
With “interference” engines, there’s very little margin for error. So, when the belt snaps, the pistons hit the valves and damage them.
On a side note, learn to trust your mechanic as long as his suggestions are consistent with your owner’s manual. 103,000 miles is at the top end for the life of a timing belt. You were definitely playing with fire.
Question: I drive a 2000 Honda Accord with 131,800 miles. There’s nothing wrong with my car yet. It has always driven smoothly and never given me any problems. However, because it’s getting old, I know that parts are going to start failing sooner or later. My mechanic suggested that I use rebuilt parts when the time comes to replace things. Would you make the same recommendation?
Answer: Thanks for your question, Leslie. Be careful with rebuilt parts. Their quality and durability have a lot to do with the workmanship of the rebuilder. And that can go both ways. I’ve seen rebuilts that I half-expected to fail within a month. I’ve also seen rebuilts that were built so well, I’d trust them as much as a new OEM replacement.
If you’re going to use rebuilts, ask the mechanic whether they’re OEM-certified and if they come with a warranty. I’d avoid any replacements (for major parts) that came with less than a 2-year warranty.
Question: I own a 2001 Hyundai Sonata with a little over 97,000 miles. I was at my local repair garage a few days ago getting the oil changed. The mechanic comes over and shows me the cap from my radiator. There was this thick, brownish sludge in it. He said the stuff was in my radiator and probably in the coolant system, too. Any idea what caused the sludge to form? Is there any reason for me to be concerned?
Answer: Thanks for sending your question in, Stephen. I’ve seen the type of sludge you’re describing. In my experience, it is caused by stagnant coolant throughout the cooling system. You should be changing the coolant every few years to keep it fresh. I’m going to guess that you haven’t done so. I suggest that you replace the coolant as soon as possible.
That’s it for today’s installment. I’d like to extend my thanks again to David, Leslie, and Stephen for sending in their questions and letting us diagnose their car problems. Next time, I’ll have a new batch of interesting automotive problems from readers to diagnose. Be sure to come back for that. Until then, drive safely.
