Starting problem Mercury 2003

I have a 2003 sable 3.0l v6

At times it will crank over but not start.

Turning off the fan, air/radio it seems to start right up, after turning off any and all elec. I have replaced spark plus wires fuel filter.

I am thinking the problem is with fuel pump or Ignition coil ???

Thanks for any help…

Clean and tighten battery connections. How old is the battery? Any check engine light on?

I agree that you should check the battery with a volt/ammeter and then check the starter draw when cranking the engine. Most likely, it has a sticker on it somewhere that says what it’s rated at. If you can check the individual cells with a hydrometer, do that as well as well as clean the posts, check and clean the clamps and take a good look at the cables. Check the stored voltage as well with your meter. A fully charged 12v battery should be reading about 13.3 volts or so.

If you can’t do this yourself, Sears automotive centers used to do starter system checks including all the above. It used to be a freebie but I think they charge $40 now, maybe more. If they find something like a bad battery and you have them replace it, they’ll give you credit for the electrical test.
Take it light. Mark
M

Other than the choice of Sears that was good advice. I would suggest a auto parts store for the test of the battery and charging system, the owner hopefully can clean the contacts.

While it may vary from store to store, overall Sears has a poor reputation.

Thanks for all The reply’s
Battery had a bad cell . I have replace the battery 4 days ago and it seems to have taken care of the starter problem.
With it cranking over good I would of replace Ignition coil next you all save money and time .
Thanks Chris