Only starts after block heater is plugged in

someotherguy

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I am in Texas and the only colors I have noticed are Black or Red for Gasoline, Blue for E15, Yellow for E85 and Green for Diesel. That being said I was in a rush one day, not paying attention and a diesel nozzle will fit right into the unleaded filler hole on the 2011 Pathfinder. I caught my error before pumping anything. My mom on the other hand put a gallon or two of diesel into the same vehicle before she noticed her mistake. It burned the diesel/gas mixture and never caused an issue. I have seen both a Sierra and a Maxima pumped full of diesel.

The really expensive mistake is DEF into a Diesel tank. Seen it multiple times on Fords and Titans where both fillers are in the same fuel door.
An even bigger mistake is gasoline into a DEF tank. A former co-worker managed this, somehow, at a station that has DEF at the pump. Pretty sure the gas nozzle is too large for the DEF filler neck on a Ram 4500, but that didn't stop this bonehead. He's the type that could never work long enough anywhere to pay down his damage claims.

Richard
 

Darkimag22

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I agree with both the coolant heater not warming the coolant much, and a faulty (or soon to be) coolant temp sensor causing a hard start issue.

How far away from the sensor is the actual heater element? Could it be warming the coolant around the sensor enough within that 5 minute time frame to see a different reading? (I’m from the south and have never even seen one lol)

Do you have an ohm meter to check the resistance of the sensor (before and after heating) or a scan tool to see what the computer is seeing as a value? ( I don’t remember the specific number but usually when the sensors go bad the computer will show a value of “-55f” I think)
Well it seems it was a failing/failed coolant temp sensor. Checked the resistance with a Fluke meter and got a reading of 3400 ohms. I'm guessing that's not ideal. Left the truck unplugged for 5 hours in -20c temps and fired right up with no hesitation.

Would never have guessed that a new coolant sensor was the culprit.
 

Darkimag22

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Very common for a failed coolant sensor to cause hard- or no-starting. What surprises me is that five minutes with the block heater plugged-in made a difference.
That's what had me scratching my head.
Ugh… it was 75 when I left work yesterday and 36 when I got here this morning
Well this morning it was -21C/-35C (-6F/-31F) with the wind chill.
 
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