Weak Cranking Power

[K1CKBAC]

Hey guys,
Been hunting down why my car won't even start and just noticed my car is really weak cranking power. When I start the car, it would crank for about 1/2 a rotation and then stops with clicking sounds. I double checked the battery for power and tested good, also tried another good battery but it still won't start. What else can cause a car to have low cranking power? Alternator grounding cable a probable cause?

[TurboJake]

Chassis grounding cables. Engine, and battery.
Smaller likelihood it's the positive cable.

The alternator does not help with cranking ;)

[K1CKBAC]

I'll double check the ground cable but it is new.

[dougie30]

Starter?

[bmw325csi]

Starter?

Isn't this the oblivious answer?

[dnguyen1963]

Oblivious or Obvious?

[dougie30]

Isn't this the oblivious answer?

Haha thats what I'm saying

[amcink]

Battery is bad

[K1CKBAC]

Update: Thanks for the input guys. Battery was fine, starter was fine. It was my ground cable from engine to chassis. Although it is only a few months old, it developed a lot of resistance for some reason.

[VAE30FTW]

Awesome! This is a good way to test as well



Did you also clean up (with a scotch pad) the mating surfaces of the ground cable? If there is a layer of rust it will have resistance. I usually coat the surfaces with a bit of dialectric grease.

[K1CKBAC]

Wow that is a great way to test. I did not put any diaelectric grease because I'll be pulling the motor for a rebuild in less than 2 months.

[VAE30FTW]

Wow that is a great way to test. I did not put any diaelectric grease because I'll be pulling the motor for a rebuild in less than 2 months.

Cool, just don't cake it up and make sure the pressure from the ground strap squeezes most of it out.

[Gregs///M]

Be sure to clean the surface of both the oil pan bolt and frame rail stud. I use a wire brush attachment on a air tool. You want nice clean shiny metal. Then secure the ground cable well.

Also do this to the mounting points when installing a new starter or alternator.