Sunnyvale Auto Repair

In September, I wrote about electric emergency brakes. At the end of the column, I told everyone to read their owner’s manual to have a better understanding of their brakes if they encounter a problem. The subject recently hit close to home. My wife drives a 2011 BMW X5 diesel that just so happens to have an electric emergency brake. I noticed that her electric emergency brake switch was getting loose, but I kept telling myself that I would order the part and install it when I got a chance. While driving to church, I looked down and saw that the e-brake switch had broken off. I asked my wife what happened, but knowing the switch was already loose, I didn’t press the subject. I also realized that I could still line up the broken tab and possibly position it well enough to make it useful. As we arrived at church, I found myself in a predicament: Should I engage the e-brake or not? In the back of my mind, I somehow thought it would be kind of a cool experiment. So I did it. At that exact ... read more

In November 2015, one of my newer customers brought in his 2011 BMW Z4 35i because the service-engine-soon light went on. He explained that the car did not idle well and was low on power. We connected the car to the Integrated Service Technical Application, because it was a post-2008 BMW, and were able to pull several codes related to the primary operation of the engine. We pulled Digital Motor Electronics (DME) codes: DME 002CF6 Throttle valve potentiometer 1 – plausibility to air mass; DME 002CF7 Throttle valve potentiometer 2 – plausibility to air mass; and 002D2E DME Throttle valve angle – intake vacuum correction. READ CODES WITH CARE But one must be careful when reading codes. It would be easy to think that there may be a problem with the throttle body, but the third code is extremely important (DME 002D2E Throttle valve angle – intake vacuum correction). The correction code indicates that the volume of air entering the throttle is not the same amount being processed by the engin ... read more

A new customer recently brought his 1999 Subaru Outback to the shop. The man said the car was overheating and making noise whenever he drove it. Because most of the time I write about complex diagnostic scenarios, I’m sure that many of you think this is going to be a column about a really tough cooling-system problem. But that’s not the case; the cooling-system problem was the typical Subaru 2.5-liter head-gasket failure. I am bringing up this problem to discuss the anatomy of the failure. MORE ON MOTORS I first must explain the different types of motor configurations. There are four configurations of internal combustion engines: inline, V, boxster (flat) and rotary. Inline engines are those with cylinders that are literally “in line” – lined up back-to-back. The most common inline motors are 4, 5 and 6 cylinders. The “V” used to describe a V6, V8, V10, V12 and V16 does not actually stand for a word, but instead the shape of the pi ... read more

I recently had two customers bring me two common problems on the same day, so I thought that it would be interesting to bring these issues to light. We had a 2004 Acura TL with a power-steering pump whine and a 1999 Toyota Camry XLE V6 with no idle when cold. I find these problems interesting because there is no built-in warning light or technical code to identify them. The Acura owner told me that when he starts the car in the morning, he hears a whining noise in the background that increases when he turns the steering wheel. Acura hydraulic-power-steering systems use a power-steering pump, power-steering reservoir, power-steering rack (rack and pinion) and power-steering hoses that tie it all together. The power-steering fluid starts in the reservoir and is pulled into the pump through the suction hose. The pump pressurizes the fluid and then delivers it to the power-steering rack. Once there is pressurized fluid at the power-steering rack, the steering wheel turns easily – even if t ... read more

Last month a new customer brought in his 2012 Subaru Forester X. He said every time he fills his wiper fluid, it leaks out almost immediately. He added that it leaks even faster when he engages the washer sprayers. We lifted the car and removed the lower-left front-fender liner to gain access to the washer reservoir. That’s when we discovered that three of the hoses were damaged – but not by normal wear and tear. Rodents had chewed them. Two years ago I wrote an article on how rodents will eat just about anything on cars. Since then we have found engine valleys completely filled with acorns, ignition wires eaten, wire harnesses eaten, under-hood insulation eaten, cooling hoses eaten and even a small mouse city – with nests – inside of a dash (perhaps using the blower motor fan as a treadmill). This epidemic seems to be getting worse. HOOD RATS Besides the fact that rodents seek a warm, dark place to sleep and nest, it was unclear to me why more and more of them use car parts lik ... read more

Last week a customer brought in her 2002 Mazda Protege5. The car came in for basic maintenance (85,000-mile service), but the customer noted that the vehicle suffered a rough idle at stoplights when warm. I told my technician to perform the regular maintenance and test-drive the car to check the idle. After driving it for approximately 15 minutes, we could not confirm the customer complaint. A common problem on this Mazda engine is that the main air intake boot from the mass airflow sensor to the throttle bodies may crack. When the car comes to a stop, the extra air from the boot may cause the idle to drop. But in this case, the boot was in great shape. We also checked the throttle plate while the air boot was off. There was a little bit of carbon buildup, but nothing that would affect the idle. We cleaned the throttle and put the boot back on. We connected the car to the scanner to check for engine codes – there weren’t any. We checked engine data, but everything was in specification ... read more

I have written several articles on the importance of scheduled maintenance, such as making sure to stay up to date with fluid intervals and filters. Failure to perform these basic services and have them performed by a qualified shop can only cost you money and headaches in the long run. Last week we had a new customer come in with his 2007 Lexus IS 250. The customer said he had just purchased the car and after driving it only 50 miles, the check engine light came on. What he did not realize is that the previous owner did not have quality maintenance performed. After connecting the scanner, we pulled four codes: P0012: Camshaft Position “A” Timing Over-Retarded (Bank 1) P0014: Timing Over-Advanced or System Performance (Bank 1) P0021: “A” Camshaft Position – Timing Over-Advanced or System Performance (Bank 2) P0022: “A” Camshaft Position – Timing Over-Retarded (Bank 2) These codes seemed unusual to us; it’s more common to see one valve timing code – not 4. If all four were correct, we ... read more

A new customer recently brought his 1999 Subaru Outback to the shop. The man said the car was overheating and making noise whenever he drove it. Because most of the time I write about complex diagnostic scenarios, I’m sure that many of you think this is going to be a column about a really tough cooling-system problem. But that’s not the case; the cooling-system problem was the typical Subaru 2.5-liter head-gasket failure. I am bringing up this problem to discuss the anatomy of the failure. MORE ON MOTORS I first must explain the different types of motor configurations. There are four configurations of internal combustion engines: inline, V, boxster (flat) and rotary. Inline engines are those with cylinders that are literally “in line” – lined up back-to-back. The most common inline motors are 4, 5 and 6 cylinders. The “V” used to describe a V6, V8, V10, V12 and V16 does not actually stand for a word, but instead the shape of the piston ar ... read more

Last month a new customer brought in his 2012 Subaru Forester X. He said every time he fills his wiper fluid, it leaks out almost immediately. He added that it leaks even faster when he engages the washer sprayers. We lifted the car and removed the lower-left front-fender liner to gain access to the washer reservoir. That’s when we discovered that three of the hoses were damaged – but not by normal wear and tear. Rodents had chewed them. Two years ago I wrote an article on how rodents will eat just about anything on cars. Since then we have found engine valleys completely filled with acorns, ignition wires eaten, wire harnesses eaten, under-hood insulation eaten, cooling hoses eaten and even a small mouse city – with nests – inside of a dash (perhaps using the blower motor fan as a treadmill). This epidemic seems to be getting worse. HOOD RATS Besides the fact that rodents seek a warm, dark place to sleep and nest, it was unclear to me why more and more of t ... read more