Q. I have a 2004 BMW Z4 convertible. To open the top there are three ways, the button on the inside, key in the door lock and remote on the key. My remote key fob only works once in awhile. I have replaced the motor and the two keys and still can’t get it to work all the time. Do you know of a good mechanic to fix this problem?
A. BMW did have a concern with this issue. The problem is that there is interference between the key fob and the receiver that is built into the mirror. The repair involves disassembling the mirror and performing a minor retrofit. Your repair shop should reference technical service bulletin number SI B 66 05 05.
Q. I have a 2005 Ford Taurus for a winter car. We purchased this car pre-owned and it had generally been pretty good. Here is the problem, it starts fine when the temperature is above freezing, however when it goes below freezing the first start in the day- well it just doesn’t start. For a while, once started (second or third try) it was fine for the rest of the day. Last winter it started doing something else. It may or may not start the first time out, but then I could find myself anyplace and when I turned the key my dash would light up like a Christmas tree and it just would not turn over. I would almost get it to the point of flooding it before it finally did start. So being unpredictable and worried about getting stuck someplace I gave it to my mechanic for a few days and of course nothing happened. It is getting cold out there do you have any suggestions?
A. There are so many possibilities with this car. Some common problems areas have been the idle air control motor sticking, the crankshaft sensor, low fuel pressure and even the antitheft system. It will just take time (and money) to diagnose the various components. If I had to take a wild guess I would look carefully at the idle air control motor some issues.
Q. We have a 2003 VW Golf that is in overall excellent condition. Unfortunately, due to the timing belt breaking and despite a new one being installed, the dealer discovered that the belt breaking ruined the engine. They said a new or rebuilt engine has to be installed. It has approximately 118,000 miles on it. Do you know of any local garages that buy cars for their parts?
A. If the car is in “overall excellent condition” I think it would make sense to put a used engine in the car. The labor cost will be 8-10 hours plus the cost on a used engine. Used replacement engines on-line seem to be about $1000. Putting your car back in running condition could put the value at $4000. A VW Golf that needs an engine might bring $500. If you decide to sell the car as is, I would look for independent shops that specialize in Volkswagen repairs. These shops are likely to give you the best price for your car.
Q. I was wondering what your thoughts are on the complete redesign of the Ford Escape?
A. The previous design was one of the best selling small SUVs sold and the latest design certainly gives the Escape a more contemporary look and feel. The 2014 Escape handles well, gets good fuel economy and has decent power. The performance and fuel economy only get better when equipped with the EcoBoost engine. I also found the interior to be of higher quality and generally more upscale than older models.
Reader comment: A couple of months ago you answered a reader’s question about putting a Prius into neutral on downhill runs in order to improve fuel economy. Your answer was rather vague and did not address the uniqueness of the hybrid system. Placing a Prius in neutral disengages the transmission and will use normal wheel braking to slow the car. By leaving the car “in gear” the hybrid system will utilize the electric motors in reverse to both limit and slow the speed of the vehicle and also to regenerate the battery charge, resulting in better fuel economy overall, since the increased battery charge will be used to avoid burning gas at other times. The reader’s claim of a 10mpg increase was probably based on short term measurements and observation of the gauges, and not by long term tracking over consistent and varying conditions. Also note that the monitoring readouts of the Prius, as other cars seem to as well, over-report the mpg by as much as 10% compared to long term calculation of miles driven divided by the total amount of fuel purchased. Prius owner for over 7 years (2006 and 2012 models)John Paul, the “Car Doctor,” is public affairs manager for AAA Southern New England and a columnist for Boston.com. A certified master technician, Paul tests dozens of new cars each year and also hosts a radio show on 950 WROL in Boston (www.wrolradio.com) on Saturday mornings at 9. Need car advice? E-mail John at firstname.lastname@example.org or go to www.boston.com/cardoctor for past columns, tips, and repair help.