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Q: Hw u kno if car jump time

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Hw u kno if car jump time
My car has an automatic transmission.

When we speak of time or timing, there are two areas of our motor that must be in time. The ignition system that provides spark to our cylinders and the camshaft timing that is timed with the crankshaft. Both of these can, as you call it, jump time.

In the case of camshaft timing, it affects the ignition timing. On your 2001 4.6 liter motor, ignition is distributorless and ignition timing is not adjustable. The computer does it all. So that leaves cam timing. A simple way of checking camshaft timing is to take a compression test of each cylinder. This may or not reveal definitive results with your motor though. Your motor has a timing chain apposed to a timing belt. They can skip a single tooth that will cause running problems, but won’t make a large enough difference to reveal a problem in compression specifications. If the car does not run, it might, but there are many other variable to consider to know for sure. So that leaves two options.

The best, but most technically advanced, is to connect a graphing scanner or an oscilloscope to compare the camshaft sensor and crankshaft sensor wave forms. As I said before, this is highly advanced work that requires some very expensive hardware to perform. The other method, would be a direct inspection of the timing marks and this is very labor intensive in the case of your car.

Ideally I think you should book an appointment with one of our technicians to be sure you are going down the correct path. With modern electronically controlled cars, there are many other things that can cause timing issues. I recommend booking the following appointment with YourMechanic; car idle is rough inspection which can be performed at your home or office by an expert. This inspection seems to be the most relevant since I am not exactly clear on what is happening with yours.

Good luck!

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