Hey guys,

I have a weak initial crank when starting up my truck cold and wanted input on where I should start my troubleshooting. Unfortunately I'm at work so I can't mess with it right now.

Basically, when I started the truck, the first couple cranks were noticeably weak but then got up to normal. It went like this (truck had been sitting parked for about 3 days and it was around 50 degrees):
naaaah naah nah nah nah voom

After it started the first time, I killed it about 10 seconds later and it restarted better, more like this:
nah nah nah nah voom

I assume I would start by having the battery tested and if that is okay suspect the starter? My guess is that the battery is starting to go and not holding a charge that well which is why the initial attempt was poor but it was better after the truck had been running for a few seconds to charge it.

 

As with starting systems checks first step is to start at the battery. The initial first crank is slower due to fighting engine compression. The windings in the starter could be weak and that's why the engine is turning over slower, the battery could be weak or even a bad ground or bad battery cable.
*Check the battery-load test and keep the top clean. Its hard for a dirty battery to function believe it or not !
*use a digital multimeter and check voltage drop. The drop should not exceed 0.5 volts. If it does you have bad or weak continuity. Grounds need to be shiney! That's the only way electricity can flow through its path.
Starter should be checked. The amperge draw needs to be checked on the starter. If the amperage draw is high the starter windings may be weak.

The first start of the day is always the worst. But as temperatures get colder a week battery will be more prevalent. At 0degs a good battery will loose up to 40% of its power. But a bad battery at 0degs may not have any ommmf to fight the compression stroke of the engine

 

The first thing to check is the battery cable clamps/terminals for corrosion. Clean/grease. Then drive it to an Auto Zone or similar and have them check the battery. One or the other will solve the problem. But, you're lucky! Frequently you get no warning that the battery is failing or the terminals are corroded - you drive somewhere, get back in to go home, and nothing happens - you're stuck. But you were paying attention, so you'll get it corrected without getting stuck somewhere you don't want to be.

 

My truck was doing the same thing, Replaced the battery and all was well. Stuffed the biggest battery I could with the most CCA into the stock spot.

ALSO, don't use it too long with a dieing battery. The dieing battery messes with the charge from the alternator and strains it more than normal wear. I pushed longer and longer before buying my new battery and caused my alternator to fail.