Intermittent engine will not crank issue?

Hi,

Most certainly, you do not need to replace the timing chains to replace a cam sensor. Also, if the check engine light wasn't on, there is no problem with the sensor. If there was an issue, the check engine light would have turned on.

Now, interestingly, the idea that originally it started when you tapped the starter motor leads me to think the starter is bad. However, I have a question. When the problem occurs, does the starter engage and turn the engine but the engine doesn't start, or does the starter motor fail to do its job?

As for the camshaft position sensors, they are located on the rear/top of the valve covers. There is one bolt that holds them in place. The only difficulty is the upper intake manifold needs removed to access the left side. (I believe the right side can be done without removing it). The left side is the driver's side, so ask him which one needs to be done.

If you look below, I found a picture of the top of a valve cover and highlighted the cam sensor and bolt holding it. If he is insisting that the timing chain needs to be replaced, you may want to consider another opinion.

Let me know.

Take care,

Joe

See pic below.

Hi,

If possible, take the vehicle to a local parts store and have them scan the computer so we know what code is stored. Write the code down and let me know what it is.

Now, the starter issue may simply be a faulty starter. When it doesn't engage, I need you to check if it is getting power from the trigger wire.

If you look below, I attached the wiring schematic for the starter circuit. At the starter, there will be a heavy gauge red wire that has power at all times. Also, there will be a smaller gauge wire that is yellow with a gray tracer. The yellow/gray wire is the trigger wire.

When you check the yellow/gray, it won't have power until the key is in the start position. So, have a helper turn the key to the start position while you check to see if power is available. If it is, the starter needs to be replaced. If there is no power, switch the starter relay with a different one having the same part number to see if that is the issue. I don't feel it is a fuse related issue because it wouldn't work on and off the way it is doing.

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below. Note: I had to cut the schematic in half to make it readable for you. I did overlap the two so you can follow from one to the next.

Let me know what you find.