How
AAA Northeast automotive doctor John Paul answers a question from a reader who inherited a 1970 Pontiac.
Q. My father passed away and left me his 1970 Pontiac LeMans with a 350 cu.in. V8 engine. Could you help me on what type of gas and oil I should use? I have no idea what my dad used and I want to treat the car well.
A. Depending on how you’re going to drive it, regular 87 octane should be enough. If you hear engine knocking (detonation), upgrade to premium level. These engines were designed for leaded fuel and if the engine is all stock and you plan to drive the car every day, add a lead additive to the fuel. If it’s just a car you use to go out for ice cream on the weekend, it’s not necessary. I would use 10W-30 or 10W-40 oil. Many people with older cars use Shell Rotella T5 oil, a synthetic blend formulated for diesel engines. But any grade 10W-40 10W-30 designed for older motors is fine. Since the car is 53 years old, I would not use full synthetic oil. Synthetic oil will not cause a leak, but it will be able to detect existing leaks.
Q. When starting our 1998 Buick, the airbag light stays on. Should he? All other lights on the dashboard will come on momentarily and then go out. The car has not been driven much but has been started and driven a little over the last three years.
A. The airbag/SRS light should come on for a second or two and then turn off. The airbag system performs its own check on startup and when the system is deemed correct, it turns the light off. At this point, the airbag system and other computer components should be tested using a quality scan tool. Once you have the computer codes, you will have a better idea of how to do this.
Q. My old Chevy’s alarm goes off in the middle of the night. My repair shop told me they thought it was the airbag that was causing the problem. Is this possible, and can I just unplug the horn?
A. The alarm going off may be related to the airbag, and on some GM vehicles the problem was that the airbag cover would shrink in cold weather and activate the horn. The proper repair is to replace the airbag. Regarding disconnecting the horn, the horn is part of the security system and I would not recommend it.
Q. I have a 2019 Subaru Outback base model. Lately the radio and/or touchscreen has been behaving strangely. Sometimes when the radio is on FM it starts changing stations as if I were pressing “scan”. Once in SXM, he will leave the station and access an SXM screen. When these things happen, the screen and buttons become unusable. I’ve heard of a reset procedure that seems to work sometimes for a day or two. Also, I’m sure I used to watch for blind spots, but now I don’t.
A. Blind spot monitoring and backup sensors were an option and I recently responded to an email from a reader who thought they had lost their backup sensors. Come to find out, the car never had this feature. Regarding the touchscreen, there are dozens of technical bulletins suggesting everything from battery disconnection to multiple software updates. There was even one that simply suggested deep cleaning the touchscreen with a microfiber cloth and Sprayway window cleaner. At this point, it would probably be best to take the car to the dealership and let them verify that the software is up to date.
John Paul is AAA Northeast’s automotive doctor. He has over 40 years of experience in the automotive industry and is an ASE Certified Master Technician. Send your question to Car Doctor by email to [email protected]. Listen to the Car Doctor podcast on johnfpaul.podbean.com.
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