Your engine runs at around 200°F so your climate doesn’t change the oil recommendation. Neither does age. Stick with the recommended oil

Here’s a guide on how to read a dipstick

Doubltful that it’s caused by the oxygen sensor. Most common cause of reduced MPG is worn spark plugs. And to answer your question, no, you don’t need to replace the downstream because it has nothing to do with calculating air/fuel mixtures. Its only job is to monitor the cat performance.

Looks like a factory service manual. That’s what FSM means

Rotors don’t warp. That’s a myth. There isn’t a street vehicle in existence that can produce enough heat to warp cast iron. But disc thickness variation caused by lateral runout is what most people mistake as warped rotors. The most common cause of lateral runout is not cleaning rust off the wheel hubs and not using a torque wrench to tighten lug nuts. Anything that prevents the rotor from spinning perfectly parallel with the hub will cause lateral runout wobble and that causes opposite side rotor wear or opposite side brake material buildup. Either one causes pedal pulsation

The variable valve timing system (VVT) on an engine operates using oil pressure. If the oil is oil or has any sludge, that can cause the VVT system to not run properly and set a trouble code. Many times, you can fix that by cleaning the filter screens on the mechanisms and changing the oil. In fact, if the shop suspects the oil is the cause, changing it is the recommended procedure.

So ASK the shop if that’s whey they changed the oil before you go off the deep end and start accusing them of screwing you.

OEM, Moog, Beck Arnley, or TRW

Locate the heater box under the dash and look for a black rubber tube that comes out of the bottom of the heater box and heads down through the floor. That’s your drain. Lay a towel down and remove the rubber drain from the heater box. Be prepared for a flood of gooky water.

Any advise other than scanning?

No, because scanning for the trouble code is ALWAYS the first step in diagnosing a problem like this

The oil cooler/filter assembly on these chrylser products are garbage. They have almost a 100% failure rate. Look at them wrong and they leak. The dealer blame the oil change shops for overtightening the oil cap, but even if tightened with a torque wrench, these units still fail. It’s a horrible design and the dealers are looking to blame anybody but Chrysler. This really should be a recall item

Aquapel is a hydrophobic glass treatment product. You can buy it online. Last for about a year.

Do NOT USE oil additives.

His advice is based on the myth that all premium gas is ethanol-free. It’s not. Some premium fuel is ethanol free, but it’s not universally true, at least in the U.S. The ONLY reason to use premium gas in a small engine is if you can’t find ethanol free regular gas and the premium gas is ethanol free.

Aside from the ethanol issue, there is NO upside to using premium. It’s a waste of money and does nothing to reduce problems with your engine.

It’s important to add fuel stabilizer to fresh gas because it doesn’t work on old oxidized gas. Also, it depends on the type of stabilizer you use. There are two types of stabilizers, prevention and remediation. Prevent stabilizer try to prevent the fuel from oxidizing and forming gum deposits. The remediation stabilizers do that plus they deal with fuel that has absorbed water due to ethanol. See this article on how the stabilizers work

It’s not always about what the car is worth right now. There are other factors to consider as well, This article walks you through the reasoning process on whether to keep putting money into a vehicle versus biting the bullet and getting rid of it.

Pretty sure you don’t even have throttle linkage cuz it’s an electronic throttle body. Check your owner’s maintenance manual. You won’t find either of those in the recommended services. There’s reason for that; They’re not recommended. They’re wallet flushing services

Some RTV sealants are ready to go in less than an hour. The Right Stuff doesn’t need any cure time. Worry about the things you’re in charge of and let the shop worry about the things they’re responsible for.

First you have to differentiate between maintenance and repairs. Belts, brakes, spark plugs, suspension parts, steering parts, bearings are all predicable maintenance and you should plan for those. Repairs are things that aren’t in your maintenance guide that are unexpected. Whether to keep an older vehicle depends on the body and frame condtion and how well it has been maitained.

The Bureau of Labor Statistics will have the info you’re looking for

First, remove and clean the battery terminals and posts. Rapid clicking can be a sign of a bad connection. Then get the battery tested at any auto parts store. Average battery life is 3-4 years, so you you’re probably due

Those work, but barely. You have to push and turn at the same time and those blocks often slip out of place. The tool the pros use is somethinglike this