Sensor, battery, or what else could it be?

So now my truck is having issues starting up. But it is kind of a reverse problem of what one might think. It starts right up, no problem, first thing in the morning when it's cold outside. But if I start it up later in the morning when it's warmer outside, it takes a good 5+ seconds to start up. After I drive for awhile, then stop for about 5 minutes, it starts right back up. In fact, sometimes it starts RIGHT UP, with barely a revolution(?) of the starter. But if I stop for 10-15 minutes or more, it will take multiple revolutions of the starter before it starts up, at least 5 seconds or more worth. My mechanic friend told me it sounded like a sensor issue. Just last week I drove down to the beach to go surfing(as per usual), was out of my truck for a little over an hour, and my battery seemed completely dead once I got back. It just clicked when I tried to start it. I got a jump, drove it home-about 15 minutes, and it has just gone back to the same starting issues. This was the only time my battery went dead on me. So what do you guys think this could be? Sensor, battery, or something else? Thanks.

 

Sounds like a battery problem. Are the terminals and posts acid covered? Even if it LOOKS clean, the terminals could be oxidized, they’ll look dark or black, not always easily noticeable until you remove the posts. Often an intermittent hard to start, or no start, or clicks only will be that.

Use a battery brush to clean them. If the terminals are acid caked, take the battery out, put a little container of coke cola, dunk them. After a few minutes scrape off what didn’t come off, dunk again.

 

Thanks for the reply. I did notice there was a bit of white residue around the terminals. Should I just get a new battery?

 

Go get it tested at auto parts store where you buy your batteries.

 

You probably don’t need a new battery.

I suggest cleaning it first. Fairly simple with minimal tools. 10mm wrench, battery brush, a can of coke, small containers, maybe a pocket knife or flat screwdriver. Autozone usually carries noco corrosion prevention felt pads, I’ve seen them a walmart too. Noco makes good ones.

Loosen the negative battery terminal, pull the terminal off the battery, push it away so it isn’t touching. Now the positive terminal won’t spark and ruin your wrench. Remove the positive terminal the same way. Loosen the battery bracket nuts, move it out of the way being careful to not accidentally touch it to both battery posts. Pull the battery out. Put the containers where the battery was. I’ve found small water bottles with the top cut off works good. You want something big enough to dunk the entire terminals. Sometimes just the positive one needs cleaning. Pour the coke in the container & dunk the terminals. Brush the battery posts with the battery brush, do the negative smaller one first. Twist the battery brush like your trying to tighten it. After soaking a few minutes scrape any remaining acid off, dunk again. After awhile, they’ll look sparkling clean. Use the battery brush on the terminals, brush the positive one first. Put the battery back in, put the bracket on snug, not tight. Put the corrosion prevention felt pads on, if one is more wet put it on the positive. Reattach the positive terminal to the positive post. Since you didn’t make the bracket tight you can move the battery if necessary. Put the positive protective cover back on. Reattach the negative terminal to the negative post. Tighten the bracket.

Now see if your problem went away. If it persists, test the battery.

 

Oh I forgot to mention, when it has a hard time starting, I can smell gas. But not when it starts up regularly. Is that normal?

 

Injector leak is a possibility. Put a gauge on the fuel rail test port. Start and run for a bit and turn off. Observe pressure reading. Come back in 30 minutes and observe reading. Should be close. If it has dropped to zero, an inj has a small leak at the pintle seal and dumped the gas in the manifold and will cause longer start times due to the flooding. After a couple hours the gas evaporates and is no longer flooded. Leak is likely slow, so the 5 minute wait dumps only a bit of fuel and creates the quicker start. By 15 minutes it has dumped it all and now too much gas to kick, requiring all the revs to clear it out.

 

Oh man....I wouldn't even know how to do any of this stuff mentioned in this thread. I am so NOT 'auto mechanical' savy. But thankyou for al the replies. I'll just have to wait until I have $$, and pay a shop to check it all out for me. Thanks again.

 

To the OP, from one that has some auto-mechanical savy": Great advice on how to deal with corroded battery terminals above. No big deal and something you can definitely handle just a couple of things:

1. Safety Glasses wouldn't be a bad idea.
2. In case it's unclear from above DO NOT touch the positive terminal and any other part of the car at the same time, or you will get shocked. Same thing with your tools. If they are touching positive and then touch any other part of the car, sparks will fly. Once you get both terminals disconnected, you'll be more safe, but still you'll need to avoid touching the positive and negative terminals at the same time.
3. IMPORTANT...if your battery is wet (UNLIKELY but I've had it happen to me)....If your battery is wet, that isn't water. It's battery acid. If you ever see that, you'll want to post back here for more detailed information on how to safely change a battery that's leaking without hurting yourself or ruining the concrete floor in your garage. The last time this happened to me, I didn't get hurt, but I still have a nice battery shaped box permanently etched into the floor of my garage where the acid ate the concrete.

Good luck!