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Cold... Very cold


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Here's the smoking gun. Important lesson to be learned from this. Ohming out the cord while plugged into the block heater isn't enough. 

 

The fluke meter showed 20 ohms on the cord, which measured good. Because of the burned / weak / intermittent high resistance connection, the meter measured an acceptable resistance, however the circuit likely opened to high resistance when 120vac was applied and current tried to flow. I see this all the time at my place of work, so I probably should have thought of this earlier. 

 

The moral of the story is, if you want to be sure, measure current flow. With the new cord on I measure 5.86 amps. Perfect. I'm expecting an overnight low of -29° C. I'll know in the morning how much the injector pop pressure contributed to this problem.

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5 minutes ago, Mopar1973Man said:

I should replace my block heater cord on my truck. :whistle2:

 

I don't want to scare anybody into throwing money at parts ($35 for a cord!), but when you don't notice until it's too late, life sucks lol. Couldn't hurt to give it a quick inspection or measure current of you have the equipment.

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Well here's a plot twist. The block heater wasn't my problem. No start again this morning, block heater plugged in all night. Looks like I'm back to remote starting every 2-3 hours until either this cold snap ends, or I re pop the injectors to a lower pressure.

 

I couldn't check the ECT because the quad wouldn't connect this morning. However the grid heater cycle was <10 seconds. For reference, it's -27°C. So the block heater worked well.

Edited by kzimmer
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That seems odd how is your crank speed are you sure your batteries are good? Your grid heaters might be cycling for 10 seconds but they might not be heating adequately that's another thing you can check as well.

We often visit Canada and in the winter time we carry a propane torch with us and if it's too cold and we can't use a block heater we will end up heating up the intake horn on the engine with a propane torch, not too much though just enough.....

Otherwise if it's one of the above I'm sorry to say but you got injector problems. 

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@Me78569 anyway we could test this by writing something that would force some additional canbus or timing at startup?

 

im not convinced it’s the injectors either. 

 

@kzimmer so if you put a hand on the motor is it warm to the touch or still cold? Again I don’t be yave much cold weather experiences but seemed like with the truck plugged it would always get fairly warm to the touch.   I’m thinking you might have a problem somewhere else. Have you checked for codes again? 

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The coldest I’ve seen my motor after 90 minutes of block heater operation was a windy morning and my winter front wasn’t installed. My coolant was around 60-70°, which is warm enough to feel if it’s 0° out. Normally it was 80-90° with 90 minutes and 90-100° after overnight heating, which is why I used a timer. No point it paying the power company for 8 hours when it’s not much warmer. 

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9 minutes ago, AH64ID said:

The coldest I’ve seen my motor after 90 minutes of block heater operation was a windy morning and my winter front wasn’t installed. My coolant was around 60-70°, which is warm enough to feel if it’s 0° out. Normally it was 80-90° with 90 minutes and 90-100° after overnight heating, which is why I used a timer. No point it paying the power company for 8 hours when it’s not much warmer. 

 That's been about my experience as well.  Either way, If the motor is at or around the 50-60 degree mark he should not be having the starting problems he's having right now.  I think there's something else going on here.  @kzimmer I hate to ask but are you sure the block heater is working like it should?  I've seen broken elements before so I wouldn't rule out the heater yet.

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2 hours ago, WiscoRedkneck said:

That seems odd how is your crank speed are you sure your batteries are good? Your grid heaters might be cycling for 10 seconds but they might not be heating adequately that's another thing you can check as well.

We often visit Canada and in the winter time we carry a propane torch with us and if it's too cold and we can't use a block heater we will end up heating up the intake horn on the engine with a propane torch, not too much though just enough.....

Otherwise if it's one of the above I'm sorry to say but you got injector problems. 

 

Cranking speed is fantastic. I actually run a trickle charger under the hood, so when my block heater is plugged in my batteries get a top-up. Something I've always done with my diesels. If it's cold enough to run the block heater, I believe it's cold enough to give the battery some help. Grid heaters are definitely heating well. Ask me how I know... better yet don't, lol. And it's already been established that my injector pop pressure is making cold starts more difficult if you read earlier in the thread. I do not have injector problems per say, rather I have a pop pressure setting that is not conducive to extreme cold. I do appreciate the comments though, always encouraged. I also really like the idea of heating up the intake with a propane torch.

 

15 hours ago, Me78569 said:

I doubt the higher pop pressure effects timing that much.

 

I don't believe it's necessarily a timing only issue, but a duration and volume issue. I don't think I'm getting enough fuel to fire at extreme cold. Pop is happening later, ECM is demanding X amount of fuel. Fuel is cold, thicker. Atomization will be poor. Volume will be decreased. Engine is cold. Air is cold. All things contributing to a no-start condition. It's important to note that with the 7 x .014's at 340 bar, the truck started like summer time regardless of temperature. Now, it never got to -27° C, but I could tell the difference at -10 to -15 with my new setup. If you recall, I noticed immediately that the truck didn't start as well.

 

39 minutes ago, Carbur8tr said:

 

@kzimmer so if you put a hand on the motor is it warm to the touch or still cold? Again I don’t be yave much cold weather experiences but seemed like with the truck plugged it would always get fairly warm to the touch.   I’m thinking you might have a problem somewhere else. Have you checked for codes again? 

 

The only code I've seen is map sensor from unplugging the quad to boost. When the truck fires it runs flawlessly. Runs like it was plugged in all night - just doesn't start like it was plugged in all night. When it fires, there is very little stumble. Not a ton of smoke. Doesn't even sound like cold start 5 seconds after it starts running.

It sounds simple enough to touch the block to see how warm it is... but you have to understand how cold -28°C is. Not many people here really know the implications of a temperature like this. It's -30° C right now. Everything is so very cold, including my hands. I can't feel if the block is warm. But I'm extremely confident that the block heater is working.

 

40 minutes ago, AH64ID said:

The coldest I’ve seen my motor after 90 minutes of block heater operation was a windy morning and my winter front wasn’t installed. My coolant was around 60-70°, which is warm enough to feel if it’s 0° out. Normally it was 80-90° with 90 minutes and 90-100° after overnight heating, which is why I used a timer. No point it paying the power company for 8 hours when it’s not much warmer. 

 

Agreed. I use a timer normally. I just bypassed it for troubleshooting purposes.

 

29 minutes ago, Carbur8tr said:

kzimmer I hate to ask but are you sure the block heater is working like it should?  I've seen broken elements before so I wouldn't rule out the heater yet.

 

No worries, questions like this are absolutely what I need for a sanity check lol. I am very sure. I changed the cord, tested everything, fabricated a cheater cord and tested with an ammeter last night. 5.86 amp draw. Measured 20 ohms on the element through the cord. 120vac / 20 ohms = 6 amps. My brother has fried two in his 2007 5.9 diesel though, not uncommon.

 

I really want to change pop pressure while it's still cold out to prove out this theory... but I don't want to do the job while it's so cold out. And I also want to get data at 365 bar for Nick's injector pop data thread before I re-pop. And I need it to warm up so I can hook up to the pavement to do a WOT run, lol. Catch 22.

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I agree that fuel volume is decreased with higher pop during crank, but your atomization will be better at the higher pressure. I do wonder thou how much fuel is decreased since the injector nozzle is larger too. 

 

I also agree that the timing change shouldn't be that much, at least not enough to make that much of a difference. 

 

So if the block heater and grids are heating, crank speed is good, and it's a ***** to start I'm not sure you can blame the pop pressure either. If it starts on a 50° day just fine it should start with a block heater, grid heater, and good batteries the same. 

 

Could it be a VP issue? Or maybe a new issue since it got cold that isn't related to the cold. 

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What do it do on a no start?  Does it just crank at normal speed without a sputter?  Any smoke out of the tailpipe?   have you do the park nose downhill to verify it isn't a fuel leak issue.

 

Given the size of injector the cranking fueling command will be WAY moire than enough to fire.  The flow from the 7 x .013's should be roughly 2x that of stock injectors at a given duration command.

Edited by Me78569
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Two new batteries this year, very fast crank, and quite a long time before I crank the batteries out of juice. It's definitely 100% related to cold, and my semi-cold starts got noticeably worse when I put these nozzles on. It didn't bug me much, because the truck still started. I'll eat my words if it isn't the pop pressure. VP44 seems healthy but I guess you never know for sure. And just the fact that as soon as it fires, it runs awesome. Drives awesome. Very happy with the performance. If it makes you warm and fuzzy I could put my clamp meter on the grids tomorrow morning. But I definitely saw signs of heating from the grids. And as mentioned above, the block heater is rocking out. Also, if the block heater was messed up, the grids should get it going. If the grids were messed up, the block heater should get it running. At least that's my thought process. Time will tell. I'll try to get my data logs done in the next 7-10 days and then re-pop to 340 bar ish. Then we just have to wait for the next cold front to move in, haha.

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Just now, TFaoro said:

Does it blow smoke out the pipe while cranking? 

 

That's a very good question. I remember looking once and not seeing anything. Even when I finally get it running, there is very little smoke, at least no more than expected on an arctic temperature day.

 

Note: I did crack three injector lines on the 25th when I couldn't get it running. Plenty of fuel dumped out when I cranked. I don't think that fuel, or rather enough of it, is making it through the injectors.

 

You should have seen my 2003 Jetta TDI smoke when it started that morning. Made my dodge look like a prius.

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