jlopez07

Thanks for the tips Nuke! I took off my cai and thoroughly cleaned the tb. Fuel filter is next. I dont think its ever been changed.

tx_zstang

The car's pcm can control the voltage output of the alternator (to some extent). Most of them running will be around 14v in a car; on a bench without the regulating control, it could read higher.

I'd say you have a bad battery or it is not charging or charged (check and clean the battery cables, make sure they are tight).

Even a "new" battery can be bad, especially if it's a 'neverstart'.

teetertotter

I was at the grocery store last night, came out, and all I got was a rattling sound, when I tried to start it up. I got a jump from another fellow shopper and headed for Auto Zone at 6:30pm. Auto zone said it was the Alternator. Then drove over to the local mechanic's shop, when I need work done, and left the car in his lot. Wife picked me up and went home. The local garage will check things out and replace what needs replacing. There is 130,000 miles on my Stang or 8 years of use with current OEM alternator. Can't complain if alternator or something else after 8 years of every day use. This car will be with me for a long time!

teetertotter

Local garage mechanic called me this morning and said the alternator is functioning to specs. There is one bad cell in the battery. We replaced the battery! The OEM alternator is standing to the test of time!

Nuke

Despite the successful test, I'd keep an eye on the battery voltage every few days before you start the car (after the car hasn't been run for 12 or more hours). This will give you a baseline of how well the alternator is charging and/or how well the battery is maintaining a charge.

The OE alternators have chronically been problematic and bad alternators have passed many a test.

teetertotter

I will just wait and see if the battery drains again and if it does, I'll go ahead and replace the alternator w/o any questions. I had left my headlights on for a good 1/2 hour, which I failed to mention as reason for buzzing/rattling noise when tried to restart. Since the mechanic stated there was one bad battery cell, changing the 4 year old battery seemed like the logical thing to do right now.

Nuke, appreciate your comments!

TBuckTex

Would like to hear how its running. My '05 vert has had a problem with in gear idle (auto) being lean. It is worse when electrical is on (rolling idle when turn signal is on, not when off). This started when i replaced the alternator to an aftermarket one and replaced battery, but shows in spec. I have... cleaned TB, replaced TB sensor, plugs, coil, wires, cleaned ground wires all around, replaced fuel filter, pcv, cleaned MAF, all to no avail. Let me know if you are running back to normal!

teetertotter

My car sat in the garage this past weekend and no problem with nice immediate starting on Monday. I normally drive it every day on distances around town year round. The old battery was 4 years old and the bad one cell. Leaving the head lights on for 1/2 hour drained the battery completely. I maybe would have been able to drive it longer with the one bad cell, but might as well change it out.
My car has run like a top with just changing the plugs with no other engine work. Transmission fluid was changed at 100,000. New rear differential kit at 80,000. Just a stock engine with same spunk when bought new. Just gets the normal maintenance from my local mechanic.

I did have the plugs changed at a different garage at 100K miles and the guy talked me into putting in Bosch. The car did not run the same and less mpg too. I ran it for 20K miles and then had this new mechanic tell me it needed the factory replacement plugs. He was right and another $80.00 investment for correct plugs installed.

jlopez07

So I just got around to changing my fuel filter. Crap load of dirt came out of it. All in all, car is running better and there is no shudder

teetertotter

jlopez, ya, sure makes a difference when things are running right.
My fuel filter gets changed every 40k miles. I have a check list of things that I log in a small ring binder and keep in glove box.
There is 70,000 miles on my Serpentine belt and due for another replacement for preventive maintenance.

My battery thing was $143.00 w 800 amp or something like that. Mechanic made the decision and knows I don't skimp on anything or just want to get by. Car is 8 years old this month! People still look at it. Stang gets detailed next month now that Salt season is over with and I furnish the exterior treatment.