Q & A #54 With The Auto Specialist

Author: Car Parts Guy  |  Category: Autos and Cars, Car Q and A

Thanks for joining me again for the latest segment of the Auto Specialist. Last week, I had mentioned reading up on Toyota’s accelerator pedal problem. The publicity uproar has since died down a bit and I’m sure the company is happy to be out of the limelight (for now). From what I’ve read, repairs will be completed on all dealer inventories by late February. Meanwhile, Toyota is preparing to offer new customers longer warranties and better incentives in a bid to quell their concerns and win public support. Time will tell whether it works.

Today, we have a full schedule with three new automotive problems to diagnose. We’ll help Tom figure out why his Diamante’s engine is losing oil pressure. We’ll also help troubleshoot Julie’s misfire problem before turning our attention to Jonathan’s fuel injectors.

Let’s get started.

Question: I have a 1997 Mitsubishi Diamante with 142,000 miles on it. My engine has been acting up lately and the oil pressure warning light came on my dash a few days ago. I haven’t had a chance to take it into the shop yet, but I’ve been hearing some odd noises under the hood while driving. Do you have any idea why my car is losing pressure? And how long do I have before the loss of pressure causes major problems? I’ve been looking through your archives for the answer, but haven’t stumbled across it yet. Any advice you can give me would be appreciated.

Answer: Thanks for sending in your question, Tom. A loss in oil pressure can be caused by one of several things. The most common culprit I’ve seen are worn rod bearings in the engine. They can wear down over time, which widens the space between them and the crankshaft journals. When that space grows wider, you’ll lose pressure.

The problem can also involve the gears inside the housing of your oil pump, your pressure release valve, or a blocked oil filter. It’s impossible to tell which component is causing the pressure drop without doing some tests. Regarding your second question, have the problem checked by a mechanic as soon as you can. Don’t wait or your engine can become damaged.

Question: I drive a 2001 Nissan Altima with 115,600 miles. Since last December, my car has been missing when I accelerate. When I first noticed the problem, it only happened occasionally so I didn’t think much about it. But, over the past couple of months, the engine has been missing more frequently. It’s now doing it on surface streets (it used to only do it when I was getting on the freeway). Can you tell me why my car is having this problem? Thanks.

Answer: Thanks for writing in, Julie. Without taking a look under the hood, it’s difficult for me to tell what is causing the misfire. Here’s what I suggest. Take your Altima to your mechanic and ask him to pull any codes from the computer. If there are no codes, replace the spark plugs, filters (fuel and air), and oxygen sensor. There’s a good chance that will solve the problem. If it doesn’t, let me know.

Question: I’m driving a 2003 Honda Civic with just over 97,000 miles. I just got back from the dealership and they told me three of my fuel injectors are blocked up. They offered to replace the entire set of four, of course, but it’s expensive. So, I wanted to run this by you. Do fuel injectors usually go out this early?

Answer: Thanks for your question, Jonathan. Yes, fuel injectors can definitely become clogged by 97,000 miles. In fact, they usually fail sooner (around 80,000 miles), so you can consider yourself lucky to have gotten this far without replacing them. Incidentally, one of the factors that causes them to clog prematurely is cheap gasoline. Low-cost fuels usually lack the detergents necessary to prevent olefins from clogging the nozzle.

That’s it for today’s installment. I’d like to thank Tom, Julie, and Jonathan for letting us help them solve their car issues. Join me next time when we dig into a new batch. I’ve seen the queue and we have some interesting automotive problems coming up. Until then, drive safely.

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Q & A #47 With The Auto Specialist

Author: Car Parts Guy  |  Category: Autos and Cars, Car Q and A

Q & A #47 With The Auto Specialist

Welcome back to the Auto Specialist. Over the past several months, I’ve been answering readers’ questions about the car problems they’re experiencing. During that time, we’ve addressed issues related to engines, transmissions, alternators, and nearly every other component under the hood. The purpose of doing so is to demystify your vehicle. That way, you’ll know what your mechanic is saying as he recommends solutions. Even better, you might be encouraged to perform a few minor repairs and replace parts on your own. Doing so may be simpler than you think.

In the last segment, we helped Todd figure out a problem with his Infinity’s timing belt. We also helped Erin understand what the white material on her Accord’s battery was. Today, I’ll answer a question from Allen regarding his Concorde’s misfire and explain a leakdown test to Marla. Let’s jump right in.

Question: I own a 1999 Chrysler Concorde with 136,000 miles. For the past couple of months, my car has been misfiring. It happens sporadically and I’m not sure what’s causing it. When it first started occurring, it was only during acceleration on the highway. But, now it happens in different circumstances. Any idea what the problem is?

Answer: Thank you for your question, Allen. Misfires can happen for a lot of different reasons. One of the most common is a vacuum leak. Besides a misfire, you might also notice rough idling, stalling, and hesitation. You can check for leaks by using a bottle of propane gas and a rubber hose. Attach the hose to the gas valve and while keeping the valve open, place the other end near areas where you think there may be a leak. You’ll see the propane being siphoned in.

Aside from a vacuum leak, the misfire might be due to bad spark plugs, a failing EGR valve, a malfunctioning ignition coil, and even clogged fuel injectors. My suggestion? Have your mechanic run diagnostic and compression tests.

Question: I’m driving a 2002 Honda Odyssey and the odometer is at 81,250. Last week, I took my van into the dealership for a routine check-up. The technician said that I should have a leakdown test done. He tried to explain what it was, but I feel clueless. What is a leakdown test and why it is done?

Answer: Thanks for taking the time to write in, Marla. Here’s a brief explanation. Your engine has cylinders. Each cylinder has a piston that compresses air and fuel within a combustion chamber. A spark plug ignites the compressed mix, which generates the energy needed for propulsion. A leakdown test measures how much pressure loss there is from a given cylinder. If the loss of pressure is over 30%, that means your engine is not operating properly. Hope that clarifies what the mechanic was trying to explain.

That wraps up today’s segment. I’d like to thank both Allen and Marla for taking the time to send in their questions. If you’re experiencing a problem with your vehicle and your mechanic isn’t providing adequate answers, feel free to send your questions in. In the next installment, we’ll answer Brad’s question about his Lancer’s oxygen sensor and help Jason figure out what’s wrong with his Aurora’s brake pads and rotors. Until next time, drive safely.

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Q & A #46 With The Auto Specialist

Author: Car Parts Guy  |  Category: Autos and Cars, Car Q and A

Q & A #46 With The Auto Specialist

Thanks for joining me for today’s segment of the Auto Specialist. If you’re new to this column, please feel free to explore the archives. Over the last several months, we’ve managed to compile a fantastic library of car-related knowledge. There are questions from readers about alternators, engine problems, transmission issues, and dozens of other parts. Regardless of the type of problem you’re experiencing, there’s a good chance that you’ll find it addressed in previous installments.

Last time, we helped Josh figure out why his Infiniti’s engine refused to turn over. We also helped Marlene understand why her PT Cruiser’s head gasket kept failing. Today, we’ll answer a question from Todd regarding his Mirage’s timing belt and help Erin with her Accord’s battery. Let’s get started.

Question: I drive a 2001 Mitsubishi Mirage. The odometer is at 98,400. I have a question about my timing belt. When I pop the hood on my car and start the engine, I can see the belt, but it’s not moving. It hasn’t snapped and there’s plenty of tension on it. I just can’t figure out why it’s sitting there. Do I need to have it replaced? And also, is there a chance that the belt damaged something when it stopped moving?

Answer: Thanks for writing, Todd. My guess is that the teeth on the belt (on its underside) have been shorn off. To answer your first question, you’ll need to have it replaced. As to whether it caused damage, the only way to know for sure is to have a mechanic take a look. There’s a chance that the timing belt bent one of the valves when it failed. If that’s the case, it will impact the compression level within your engine. Your mechanic will be able to test whether that has happened.

Question: I own a 1997 Honda Accord with a little over 152,000 miles. My battery always seems to accumulate an off-white substance around the poles. It has happened with previous batteries and it’s happening with the current one. The problem is that it always causes my car to have trouble starting and even when it does start, I hear a crumbling noise. What is that white material? Is something in the electrical system causing it?

Answer: Thank you for your question, Erin. The white substance you’re seeing is corrosion. Don’t be alarmed. It happens with all vehicles. Unfortunately, it can accumulate to the point that it effects the connection between the terminals and the clamps. That’s probably why you’re having difficulty turning the engine over.

Here’s what I suggest: disconnect your battery and remove it from its carriage. Then, pour a soft drink over the terminals. That will neutralize the corrosion. Use a wire battery cleaner (you can buy one for under $10 at an auto supply store) to clean the terminals and clamps. Rinse the battery down, reconnect it, and start your engine. You should find that it starts easily. If you’re still having trouble turning the engine over, the problem may be a bad starter. But, try cleaning the battery first.

That wraps up another installment of the Auto Specialist. Thanks again to Todd and Erin for sending their questions in for the rest of us to learn from. We have a lot of great questions coming up in the queue, so be sure to come back for those. Until next time, drive safely.

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