When it is cold out, can I still wax my car? | Car Doctor
Q: When it is cold out, can I still wax my car? It is new to me, looks great and I want to keep it that way.
A: I have found that spray wax doesn’t seem to like cold temperatures. Liquid and paste wax seem to work well in the 40- to 50-degree range. I would wash a car in colder temperatures. The wax I have on hand doesn’t recommend use in freezing temperatures.
Can I mix regular tires with run-flats?
Q: In 2017 I bought a used 2015 BMW 535 with 22,000 miles. It came with run-flat tires, which I have tolerated, although I don’t care for the ride and feel of the run-flats. Although they're reliable, should I ever be stranded with a flat, I find the ride to be rough and harsh.
My rear tires are ready to be replaced. I was considering moving the front run-flat tires to the rear and replacing the front with regular tires. Once the rear ones wear out, I would replace them with normal rubber tires eventually. Is that possible, or would mixing tires affect the ride? The tires are Goodyear Eagle LS 245-40-19. If it is possible, please recommend a compatible tire that will give me the smooth ride I am looking for.
The car is otherwise in very good condition with only 50,000 miles.
A: It is never a great idea to mix tire types. It would be best to replace all four tires with the same type. Many drivers do switch from run-flat tires to conventional tires, but be aware you will want to add a spare tire and jack or some sort of “mobility-kit” in case you get a flat.
As for brands, I find myself going to online-verified purchased tire reviews. Some of the larger tire distributors allow a search of make, model and tire type. As an example, many BMW drivers like Michelin Pilot Sport, Bridgestone Potenza and Goodyear Assurance Comfort Drive, all of which I would recommend.
Why is my Audi Q5 using so much oil?
Q: My wife has an Audi Q5, purchased new in 2015. The car has mostly been serviced at the Audi dealership. It currently has 58,886 miles.
Recently, I’ve noticed it has been consuming about a quart to a half quart of oil every six to eight weeks. I’ve Googled this issue and found there was a class action lawsuit brought against Audi for excessive oil consumption for models prior to 2015, and that Audi will test each vehicle to determine whether the car falls under the settlement. The settlement is to bring the car in for top-ups when needed (which to me is ridiculous).
I’ve checked the driveway for leaks and found none. There is no indication of smoke coming from the exhaust pipes. Can you offer other possibilities that would cause such oil consumption and suggest ways to fix or diminish the issue?
A: Audi considers one quart of oil used in 1,000 miles normal. The reason, typically, is oil leaking by the piston rings and burning through normal combustion. At this type of use, as well as the type of oil used, you won’t typically see any tailpipe smoke. At this point, there is nothing you can do, other than check the oil regularly and add as needed.
BMW is running rough and giving error codes
Q: I have a 2006 BMW 650i. The car is in mint condition with 40,000 miles and has never had an issue. In the past, I rarely used the car, but now I'm using it several times a week. It seems the car now has a rough idle at times. When stopped at a light, sometimes it runs rough and shakes, and other times not. There are no engine codes or check engine light.
The car has original spark plugs. I do use Textron fuel cleaner several times per year and only use premium fuel.
The other issues are the following error messages: active steering malfunction, drive control system, parking distance controller (PDC) malfunction and start off assistance inactive. Any thoughts on all of this?
A: I would start with a look at the plugs. For spark plugs, 15-plus years is quite a bit. At the same time, I would be looking for vacuum leaks and carbon buildup at the throttle plate.
The other issues are interesting. The active steering malfunction and drive control system typically are caused by a faulty steering angle sensor. This could also be affecting the PDC operation.
The start off control typically lightly applies the brakes so the car doesn’t roll at a stop. It appears that these systems all run through the same module. This could indicate a faulty module or even a poor ground to that part. At this point, you would need to check for specific codes and see what sensors are working properly.
John Paul is the AAA Northeast Car Doctor. He has more than 40 years of experience in the automobile industry and is an ASE-Certified Master Technician. Write to John Paul, The Car Doctor, at 110 Royal Little Drive, Providence, RI 02904. Or email jpaul@aaanortheast.com and put “Car Doctor” in the subject field. Follow him on Twitter @johnfpaul or on Facebook.
This article originally appeared on The Providence Journal: When it is cold out, can I still wax my car? Ask AAA's Car Doctor
