Cold start weak battery sound

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Kjz3Ro

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I asked about TB cleaning because sometimes cleaning fluid can get by butterfly shaft & damage electrical motor so rule that out.
Best to remove Pulsar & rule that out.

So wth, I get to my truck leaving work last night and it didn’t start too bad at all and the check engine light went off.. Truck ran great all the way home so now I’m really confused..
 

crackerjack1957

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So wth, I get to my truck leaving work last night and it didn’t start too bad at all and the check engine light went off.. Truck ran great all the way home so now I’m really confused..
Clean connections & check if they are loose.........just a thought.......don't forget to disconnect battery.........could get expensive if you don't
 

daveray9

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Did you capture the CEL code before it cleared?

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BadHemi2014

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I breezed over all the posts and i didnt see anyone mention or ask what octane rating you use. I saw that you mentioned you use premium gas, did you mean top teir gas or high octane gas? Because high octane requires more energy to ignite and although it idles fine, that initial spark flash may not be up to ***** to fully ignite for an even burn. Uneven burning would put stress on a piston on its way down for the powerstroke.

Imagine someone getting a clean right hook to the head in slow motion, the head moves and the face has to catch up. Thats the best way i can describe it anyway

Well cars can now detect knock etc more efficiently now and can adjust spark timing for it.

This is where i believe your hiccup is occuring, the time between the first uneven burn and the adjustment of the spark timing. If the uneven burning is corrected once the engine finds its rhythm it will adjust back for efficiency and you wont even notice. Otherwise i believe it would throw a code

I maybe way off but if the fix is as simple as filling up with midgrade, while its cold out i would give it a shot.

high octane is the cause of many problems for people. They hear it burns hotter and it cleans the carbon and makes the engine run better etc. high octane is designed FOR high performance engines, it dosnt MAKE an engine high performance.

This is interesting. I always run 89 but I used 93 for the last 2 tanks just for gits and shiggles.
I noticed this same hesitation the OP is experiencing now that we've had a few cold mornings. I'm pretty sure it wasn't there before. I'll see if it goes away with 89.
 

crackerjack1957

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Unbelievable........LoL
 
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ToxicFire

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So wanted to post a update here.

So 3 days ago i was down to 1/4 tank of fuel so went and filled up with regular 87 fuel.Let vehicle sit for a few hours,cold start and it was NORMAL.
Next morning cold start Normal again.

At this point i thought while its not freezing out here yet i would check my pcv valve and just make sure it was good and give it a cleaning and clean the throttle body maf sensor ect.
The pcv valve was actually pretty clean 1 drop of oil and the thing looked almost new.
Throttle body also pretty clean just a little black on the side but that was it.

Anyways this morning 6am cold start and again truck started NORMAL. So it has to be due to the fuel. Weird that a 91 fuel would give that starting issue but on regular 87 no problem.

Wont complain though as the price difference between the 2 grades of fuel is between 20 and 30 cents per liter haha.
 
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ToxicFire

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Well thought I would do a little update. The weird start issue is back again.yesterday and today cold starts had the issue.


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ChevySlayer69

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I just switched again on last gill up to midgrade 89 to see if it would help but same results.


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Yeah... just run 87 and you won't have the issue and definitely wont' harm the engine. Seems crazy but 87 is more combustible than 89 or 91, and the startup is computer controlled. My theory is this is a programming issue and not a mechanical issue.
 
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ToxicFire

ToxicFire

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Yeah... just run 87 and you won't have the issue and definitely wont' harm the engine. Seems crazy but 87 is more combustible than 89 or 91, and the startup is computer controlled. My theory is this is a programming issue and not a mechanical issue.
I had the issue in 87. Last couple weeks been 87 and had issue so thought I would try 89 yesterday but still same issue.

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daveray9

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Ugh that sux... knock on wood mine never came back after the PVC change.

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ram1500rsm

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Here's a quick video.

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My 14 does the same on cold starts minus the lifter slap (she has some slap from every blue moon to red moon :)). I don't remember when it started doing it. Bought the truck used with 40k. I had my fuel pump replaced later on (not because of the start issue but because the fuel sensor went band) and she stopped doing it for couple of days than it started doing it again. 94k miles now and so I don't sweat it. I run 91 octane only. (I tuned her myself) and my air filter is stock, no cai no engine mods. New battery also did nothing. Not sweating it one bit as I don't think is a big deal at all.
 
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