Car will not start intermittently while in PARK but always starts on NEUTRAL.

ANSWER : Hi there, thank you for writing in and providing a detailed description. I’d be happy to give my insight on what to do next.

I would make the same conclusion about the neutral safety switch. I think Pep Boys made the right call. I admit, I don’t like to call a part bad without being able to duplicate the problem, but anytime a customer states their car starts in neutral but not park, we replace the neutral safety switch. I can’t recall a time that this move was wrong.

The intermittent nature of your problem does’t change this diagnosis either. The same electrical connection can work one moment and not the next. Electricity works at the atomic level that we as humans can’t directly observe, which is why we have tools to do electrical testing. Your tow truck driver got it correct.

Hope this helps and best of luck! If you’d like help replacing your neutral safety switch, consider having one of our expert automotive technicians come to your home or office to do it for you.

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 : The neutral start safety switch could be misaligned or a fault in the linkage and./or cable could be contributing to the problem because "Park" is not actually reached when you move the shifter. The whole mechanism from the manual lever on the transmission up to shifter will have to be inspected. The manual lever should be inspected separately inasmuch as you indicate abnormal resistance in certain gear selections. In addition, it sounds like the shift interlock may not be functioning. The recommended service to obtain a diagnosis of all of these issues is a shift linkage/interlock inspection. If you request that service, 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.

ANSWER : Hello – if your starter successfully cranks the engine in Neutral, but not in Park, the starter itself is likely just fine. The problem is with the "Neutral Safety Switch", sometime called a range selector switch. This is the component that ensures you are either in Neutral or Park to start the engine. It has likely failed, since it is not recognizing the shifter being in the Park position. I would recommend replacing the Neutral Safety Switch by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

ANSWER : Hello. It sounds like your transmission position sensor is failing. This sensor sends a signal to the computer to let it know what gear the vehicle is put in and allows the vehicle to start in park and neutral. It sounds like the park part has failed. It should continue to start in neutral as long as it does not fail completely. If you want to have this taken care of, consider YourMechanic, as a certified mechanic can come to you to [diagnose why it will not start in park] https://www.yourmechanic.com/services/car-is-hard-to-start-inspection

ANSWER : Your MAP sensor is an important input for your computer. It helps determine the load on the engine to calculate the correct amount of fuel to inject. It sometimes takes a few seconds for the vehicle to realize that the sensor is not producing a good signal.

At that point, it will use other methods to determine the fuel rate, such as pre-programmed fuel maps, throttle position, etc. I would suggest replacing the MAP sensor and retesting. If you would like to have it checked first, a certified technician from YourMechanic will be able to scan your vehicle and test components to determine the root cause of your starting issue before making a repair.

ANSWER : Hi there:

Sometimes when you have problems starting an engine initially it is caused by a restriction in fuel flow; caused either by clogged fuel injectors or the throttle body that needs to be cleaned. Once the fuel starts to flow and engine warms up, it’s much easier to start. However, it could also be an air filter, EGR valve or other components that causes this issue as well, which is why it’s best to have a professional mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of this issue.

ANSWER : Hello. Thank you for writing in. There are several reasons your vehicle may only start when jump starting. The first and most common is a build up of resistance that is causing you to need a boost of voltage to get the engine started. This may be due to poor battery cables, a bad ground connection, a poor starter solenoid, and a couple of other issues. The first thing you want to do is perform a visual inspection of the starting system. Make sure there is no corrosion build up in the battery cables. You can also check the resistance across these wires and make sure you have a solid connection between components. You then want to make sure the starter solenoid is doing its job. It is responsible for taking the small amount of electricity sent by the ignition and turning it into a huge electrical charge that is strong enough to push over the engine with the help of some gear ratios in its favor. Do some more testing, and stick to the basics before assuming its something seriously complicated.