It cranks doesn’t start new batteries, oil pressure switch new pmd, new injection pump. new alternator, new glow plugs.

ANSWER : Hello.

A crank but no start condition can be caused by many things. A few common causes are a faulty crank position sensor, or issues with the fuel system. The crank position sensor is used in the engine’s fuel calculations, and in some cases it’s failure will disable the engine.

It may also be possible that there is issues with the fuel system that are preventing the engine from running. If the fuel pump or injectors have an issue the engine may not run correctly, or at all. It may also be possible, for either case, that the issue may be wiring related.

I would start by trying to determine if the engine is getting fuel and then going from there. If you need assistance with these checks, consider YourMechanic, as one of our mobile technicians can come to you in order to diagnose your starting issue firsthand for an accurate repair.

ANSWER : The fuel pump will not stay on if you loose oil pressure. This is why it is shutting off. The loss of oil pressure may be from bad crankshaft bearings or camshaft bearings. The engine oil pan should be removed and the oil pump needs to be checked to ensure that you put in the pick up tube seal to the pump and connected the pump to the block. Then remove at least one main bearing cap and inspect the bearings for excessive wear and crankshaft damage. If you need some help with this, consider YourMechanic, as a certified technician can help diagnose the issue with your oil pressure firsthand and help you fix it accordingly.

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 : Checking all the fuses was a good move. I would also want to put a scan tool on it and check for diagnostic trouble codes (DTCs) as well as seeing the data that the computer is seeing.

A fuel pressure test would be a good idea to verify correct pressure and so that you’d be able to eliminate that possibility. It should be 58psi on your Magnum.

I also recommend getting your battery tested (I know, it’s new, have it tested anyway) and be sure it’s charged to at least 75%. And yes, loose battery cable connections can result in electrical problems.

If you need some assistance with this, consider enlisting a certified mechanic who can perform the checks I’ve mentioned and diagnose your starting issue firsthand. The mechanic can then perform the necessary repairs once the problem has been isolated. Good luck.

ANSWER : Hi there. Anytime you have an excessive oil pressure issue, it’s common for the ECU to store an error code that disables the ignition system to prevent internal damage to seals, gaskets or the engine components themselves. It is quite likely that the reason it won’t start is due to this error code or an ignition system failure; perhaps a crankshaft or cam position sensor; as they tend to be susceptible to oil pressure issues. The best way to diagnose this is to have a professional mechanic complete a check engine light inspection, so they can download any stored error codes, clear them and determine if your issue is resolved or mechanical in nature.

ANSWER : Hi there. It looks as if you have covered most of the bases. However, it is possible that you may have an exposed or faulty ground wire, damaged ignition relay or starter relay. It is also possible although unlikely, that something in the timing system is causing the timing to be too far retarded, which can cause starting issues you’ve described. This might be a case of chasing parts only to have a different issue pop up, so it might be a good idea to have a professional mobile mechanic come to your location and complete a car is hard to start inspection.

ANSWER : Check the exhaust system for any leaks before the oxygen sensors. This can contribute to having more oxygen in the exhaust stream causing the sensors to register a false reading. If there is no leaks in the exhaust, then check the engine for any vacuum leaks. Look at all of the vacuum lines, the intake gaskets, and the brake booster. A vacuum leak will cause the engine idle to accelerate fast and also cause the engine to stall when the computer brings the idle down. If you need further assistance with your engine stalling, then seek out a professional, such as one from Your Mechanic, to help you.

ANSWER : Hi there. Check the spark plugs and see if they are worn or burned. If the plugs are good and they have a good spark, then the engine compression could be low causing a no start situation. If the spark plugs are not emitting a spark, then the crankshaft position sensor could have failed or disconnected. Check the crankshaft position sensor wiring harness and make sure that its plugged in. Check the sensor and make sure that its not broken or damaged. If you need further assistance with your engine not starting, then seek out a professional, such as one from Your Mechanic, to help you.