Quit running, but starts after waiting a while?

ANSWER : Hi there. There could be two problems here. It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery. The second problem could be that your alternator is bad and not charging your battery, in this case you will need to replace your alternator. Both the battery and the alternator can be tested in your car. If you would like to have the car checked for you, a certified professional from YourMechanic can come to your car’s location to diagnose the starting problem and proceed with repairs.

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.

ANSWER : Hello. The stalling issues you are having may by caused by a variety of issues. Typically these symptoms can be blamed on fuel, spark, or air. Fuel and spark being the most common systems to fail. Starting with the air filter and cleaning the carburetor were good steps to start. You need to take a better look at the spark system. The spark wires can be tested to make sure the plugs are receiving the voltage that they need to be. You can also test the fuel system by spraying some starter fluid into the air intake. If this helps the engine start and run better than before, then you know you have a fuel delivery issue. This may include the fuel pump, fuel filter, injectors, or a clogged fuel line. The shaking is due to the improper combustion happening in the engine. This will be corrected when the engine is running properly. More testing is the only way to know definitively what the issue is.

ANSWER : Hi there, thanks for writing in. I’d be happy to help. It sounds like you should disconnect the connector to the fuel pump and inspect it for any signs of getting hot. The female connections may be too loose on the fuel pump and lose contact after running and getting hot. If there are indeed any signs of problems, then I’d suggest replacing connector and adding dielectric lube to pins before installation. This should solve the problem, but if you continue to experience issues, feel free to reach out to us for help again.

ANSWER : Your vehicle has something called a neutral safety switch that will prevent the vehicle from starting when it is in any gear position other than park or neutral. Occasionally, this switch can malfunction causing the car to stall as soon as you put it into any gear. This switch usually also monitors gear selection data as well to transmit back to the computer. This switch is connected to the starter solenoid which allows it to complete the starter circuit only when the transmission is in park or neutral. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

ANSWER : Hi there. If you have not replaced your EGR valve, mass air flow sensor or the TPS on your Blazer, you might want to start with these repairs. It is also possible that the throttle body itself is damaged, especially if you’re able to start it on fluid. If you want to avoid chasing parts and repairs, the best solution may be to have a professional mobile mechanic come to your location and complete a car is hard to start inspection.

ANSWER : It sounds like your starting issues may be linked to a problem with air metering or fuel delivery. A clogged or malfunctioning idle air control valve may show some of the same symptoms you are describing. The idle air control valve can be stuck in a cold start position which may work well if the car has been sitting a few hours, but as the engine warms up there must be a regulation in airflow. Consider hiring an experienced technician like one from YourMechanic who can come out for a closer look at your hard start situation and offer a more personal diagnosis.

ANSWER : Hi There,
What you are describing sounds like a common problem with ignition coils failing related to what is known as "heat cycling." Ignition coils are prone to this type of erratic functioning or heat cycling when they are beginning to fail due to the temperature fluctuations under the hood which ultimately cause them to shut down causing the car to only run after cooling down for 30-40 minutes. Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeatedly The insulation develops small fractures that open when heated and close when cooled. When open, they allow shorting of coil windings and decrease or eliminate the coil’s ability to function. This process will repeat itself continuously until the coil ultimately fails completely and must be replaced. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your ignition system.