Unusual Problem, Rough Idle in Extreme Cold

[JayT]

My ranger had not been started in a couple of days. It is a 2003 with 2.3L 4cyl, and 5 sp manual tranny. This morning it was around 10F out. I turn the key and it starts right up but idles really rough. I got out to check under the hood and noticed thick dark gray smoke coming out of the tailpipe. It smells rich. I shut the engine down, and opened the hood to see if anything is amiss. I suspect snow had maybe clogged the air intake, but no. I can see no reason for the problem. I got back in and it started right up and idled smoothly with no smoke.

I went for a drive and during the drive, it began idling roughly while at a light, but not as bad as earlier. That only happened one time. Otherwise it idled and drove normally.

My guesses are:
1. A sensor was stuck in the wrong position due to the cold.
2. Water in the gas. (could that make all that smoke?)

Does anyone have an idea of what is going on with my ranger?

 

[arco777]

Most sensors are electronic and won't be affected by the cold. However a failing one could possibly have the computer confused.

Pull check engine light codes (light may not have come on but codes may still be stored) and report back. May an IAT sensor going bad?

Less likely but could be bad gas that had some water in it. Couldn't hurt to put in some HEET additive, which would help "dry out" the fuel. When I used to ride snowmobiles that was a common problem on cold days with questionable fuel, and I carried a bottle of HEET at all times which never failed to solve the problem. It's sold at Wal-Mart for a buck or two.

 

[JayT]

Thanks. I have not gotten the codes pulled yet, but the problem has not recurred . I will add some gas line drier. I wonder if I can just use rubbing alcohol. That's all HEET really is, isn't it? All vehicles get some condensation in the gas tank, so I should have been putting some in there every 4 tanks or so anyways in winter.