Ran low on coolant, now starts rough/rough idle that mostly clears

[1.0Egg]

Last night I was driving and my engine temp came close to overheating. I had a cracked coolant tank last year so I remembered its signs. I filled the coolant reservoir twice and it drove fine for the hour ride. I woke up this morning and I was met with a slow start. After 3-5 seconds the engine started, but it sounded and felt as if it was only running on one cylinder.

I turned the car off, turned it engine back on. I’ve had a bad start or two in the past where it produced a misfire until I restart the engine.
To no avail, it still sputtered... I let it run and gave it some gas. Tho misfire(s?) gradually went away as the engine rpm leveled out. I left it run and topped off the coolant one last time before I tried driving it.

It drove fine. I stopped for gas, when I turned the engine on I got the same slow start. I did see once a white cloud come from the exhaust when I did not give it gas when starting.

I have a bad exhaust leak. Directly after the flex pipe the exhaust is snapped in half… it’s been like this for 2+ years. Money has been tight and its an an expensive part and I dont know a welder that good..

Any advice would be greatly appreciated.

 

[Handy Andy]

When you run low on coolant - this may mean the engine needs more service than you can afford - the coolant prevents the car from overheating and when it runs low - the head gasket can fail causing these slow start conditions until it warms up. The compression and combustion (power) strokes push air past the seal into the coolant and so its' forced out thru the tank and any other weak seal - leaving you with having to add more coolant on a regular basis - which will get worse in time - to a point where you can't start the car due to a bad coolant leak.

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The sputtering sounds like the coolant has leaked into the cylinders when the engine is off - from that bad gasket seal and as it warms up - it smooths out the idle from the heat of the block expands and helps reestablish some seal and pressures in the cylinder itself helps to keep out the coolant from getting into the cylinders and causing the mis-fire. The Slow-turn starts are another level of clues as to the condition - from water (or coolant) in the cylinder affecting compression - a process of hydro-static water lock - this isn't a complete diagnosis but it can help explain the problem.