When I come to a slow stop, my car starts rocking back and forth.

ANSWER : Typically this type of concern would come from bad misfires as the engine and transmission internals are likely the only parts of the vehicle in motion while you are stopped. Misfires would normally cause a check engine light so you should have the engine mounts, braking and suspension systems checked for problems. A faulted engine mount could cause the engine to rock back and forth and you would feel this motion inside the cabin. Consider hiring an experienced technician like one from YourMechanic who can come out for a closer look at the vehicle to offer a more personal diagnosis of your braking or suspension concerns.

ANSWER : Hello, thank you for writing in. It is difficult to determine the issue without some more information. To start, when the check engine light illuminates, you want to scan the vehicle for diagnostic codes. These are what set the check engine light off, and are meant to tell the driver what the computer has detected is wrong. Codes can be pulled at most automotive parts stores, and by most technicians. Once you have that information you can focus in on one component or system. If the engine is truly overheating, then you want to start by checking your coolant and fluid levels. For more help with diagnosing and resolving the issue, contact our service department to schedule an appointment.

ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : Hi there:

If you recently replaced your battery, the issue may be caused by a malfunctioning alternator or other electrical component that comprises the charging system on your Nissan Sentra. The best way to find out which item specifically is faulty, is to have a professional mobile mechanic complete a car is hard to start inspection. This will allow the mechanic to determine the precise source of what’s going on with your Sentra and recommend or complete the right repairs.

ANSWER : Hello, thanks for writing in. These types of issues can be frustrating and hard to diagnose. Most of the time though this will be caused by a fuel system problem. It can either be a failing inertia switch, a failing fuel pump, or a fuel relay issue. These are by far the most common causes of this on your engine. It can take some time and some testing to find this problem if it is not occurring while it is being tested. If you are planning on having this fixed, consider YourMechanic, as a certified mechanic can come to your home or office to inspect, diagnose, and make or suggest repairs for this.

ANSWER : Hi there. Typically what you are describing is an indication that a tune up service is due. As the vehicle’s ignition and fuel system components age, they will collect excessive levels of carbon deposits, which makes it more difficult to ignite the fuel / air mixture in the cylinder. This is why it takes a few seconds of cranking to actually fire up. A traditional tune up includes replacing the spark plugs, plug wires, distributor cap, rotor and coil packs. It also includes cleaning the fuel injectors, the throttle body, and possibly replacing mass air flow sensor. However, there could be other components that are damaged that are causing this issue; so before you replace any parts, I would recommend having one of our professional mobile mechanics come to your location and complete a car is hard to start inspection; so they can pinpoint the source of your issues and ensure the right repairs are made.

ANSWER : Hi – first task is to read any problem codes, whether the Check Engine light is on or not. Most auto parts stores will do this for you for free on a "time-available" basis. Any codes extracted are useful for diagnostic purposes. Based on your symptoms, the throttle position sensor is a leading failure possibility. A malfunctioning idle air controller could also cause the unpredictable idling issues, but not a shut-off while driving. I recommend a car stalling inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

ANSWER : Of course, don’t switch gears without being fully stopped, unless your Owner’s Manual or the manufacturer has alternative advice. However, the gear shift issue has no relation to the no-start problem you are describing. Inasmuch as you only have 6,000 miles on the car, the "constant on and off" that you believe has occurred is meaningless in comparison to the expected total vehicle service life. That is, assume what you perceive as "constant on and off", during merely 6,000 miles, might be equivalent to using the car "normally" for three years. A new car should be trouble free for at least 5 years, unless there is a defect, so your "constant on and off" is not a causal factor for any fault on the vehicle. What you might have is a defect in the ignition switch, or perhaps the immobilizer system, but if the problem is not in the switch itself, clearly there is an electrical problem.

If your vehicle is under warranty, by law the dealer MUST repair the issue you are describing within a prescribed time frame and number of "attempts", otherwise the dealer will run afoul of Federal and state Lemon Laws that give you very specific rights, and recourse (contact an Attorney; we are Mechanics, NOT attorneys). Consequently, if the vehicle is still under warranty, to save yourself money do be sure to seek a resolution from the dealer. If the vehicle is not under warranty, obviously a certified Mechanic from YourMechanic could identify the electrical fault and resolve this for you. If you want to go that route, please simply request a no start diagnostic -electrical system and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.