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Hard Start When Cold

1605 Views 8 Replies 5 Participants Last post by  Sandman76
My truck is hard starting when cold. It's OK in the morning when plugged in but after work (when temps are below freezing) it sputters until I hit the gas then stabilizes. It is putting out alot of white smoke when sputtering. Once it stabilizes it runs fine. Any ideas?
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use some tcw3 2 stroke oil, go up to your fuel filter and bleed of any water that might be in there and when you do get it started just let it worm up a bit before driving
 

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My truck is hard starting when cold. It's OK in the morning when plugged in but after work (when temps are below freezing) it sputters until I hit the gas then stabilizes. It is putting out alot of white smoke when sputtering. Once it stabilizes it runs fine. Any ideas?
I had to do the high idle mod switches and i have to wait till the engine reaches something about 140 before i will move it and its fine.

white smoke on a unplugged truck in the cold is fine.


The sputtering is strange, could be a timing issue with the VP, do your grid heaters cycle?
 

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Discussion Starter · #4 ·
Grid heaters are cycling OK. It will stabilize as soon as I hit the gas. It's kinda like starting a carbureted gasser.

I was worried about the VP? It's got 200K miles on it and had a weak lift pump behind it for an unknown amount of time.

I guess what I should have asked is if this could be a sign of the VP failing?
 

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Grid heaters are cycling OK. It will stabilize as soon as I hit the gas. It's kinda like starting a carbureted gasser.

I was worried about the VP? It's got 200K miles on it and had a weak lift pump behind it for an unknown amount of time.

I guess what I should have asked is if this could be a sign of the VP failing?
it sounds like the diaphragm is torn inside your VP, as for it failing you won't know until the smoke pour out and your start throwing codes. Does it pour out white smoke for a while when its cold out, the tale tell sign is when it smokes when its plugged in.

you should look up moparmans delay fuel pressure relay and that might solve the hard starting.

and if the rpm's are jumping up and down by 50rpm's or so i think that is normal, mine does the same in the cold.


these trucks unlike gassers don't like to move until they have some warmth inside the block, they have no assistance in igniting the fuel so they need to stay warm, or warm up before they move.
 
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Discussion Starter · #6 ·
it a fair amount of smoke until the idle stabilizes, more than it used to be anyway 2-3 seconds worth of heavy white smoke. It hangs up around 450 RPM. I usually tap the gas which brings it up and then it's ok. I bought the truck new and have been through several winters with it. This is definitely something new.

I'll check out the delay from moparman.
 

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how cold is cold????? could one of your grid htrs be burned out...... heres a trick to try, when things get into low 20s or teens out here, I cycle the grids twice. Turn the ignition on, and let the grids do there thing, when they shut off, usually 20-25 sec turn the ignition off count to 2 then cycle it again, the grids will turn on agian for about 10 sec, when they shut down, twist the starter. the initial heat of the grids is sometimes not enough to get the combustion chamber to be able to preheat both the fuel and the incoming cold air. below 0*F mine will stumble and sputter a bit and blow gray smoke,,,, above 15-20*F it wont.
 

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Discussion Starter · #8 ·
Seem to happen in the 20's or lower.

I'll try to cycle twice next time and check the grids. thx
 
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