Yo Gerrad,
Do see any loss of coolant in recovery tank?
Is oil evident in coolant?
Symptom Chart — Engine Cooling
ENGINE COOLING
Condition Possible Source Action
Loss of Coolant
Damaged radiator.
Damaged water pump.
***Loose/damaged radiator hoses.***
***Loose/damaged heater water hoses.***
***Damaged heater core or tubes***.
***Damaged radiator overflow hose***
***Damaged engine gaskets.***
Damaged radiator coolant recovery reservoir.
Internal engine coolant leak.
Since you hear hissing after you shut her down, combined with apparent coolant aroma, suspect engine is possibly overheating and/or leaking coolant.Even though you started it briefly, how was temperature gauge looking during driving and when you turned it off?
In case you do detect coolant and can'take see the source, consider doing PRESSURE TESTING COOLING SYSTEM
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Here is a summary of EXHAUST smoke symptoms and causes: JUST IN CASE YOU SEE EXHAUST SMOKE WHILE STARTING ENGINE IN MORNING OR SOMEONE DRIVES IT AWAY FOR YOU TO STAY BEHIND AND OBSERVE:
Less $ first (less worries as well!)
Blue/Gray Smoke:
PCV System: A stuck closed PCV valve will cause excessive crankcase pressure resulting in blue/gray smoke.
Oil burning in the combustion chamber. Pull a few spark plugs & ck iaw Spark Plug Diagnostic Chart
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Oil Deposits Symptoms: Oily coating caused by poor oil control. Oil is leaking past worn valve guides or piston rings into the combustion chamber. Causes hard starting and misfiring.
Valve Seals: Leaking valve seals will cause blue/gray smoke at startup because oil leaks past the seals into the cylinder after the engine shut down.
Valve Guides: Excessive clearance between the valve stem and the valve guide allows oil to leak past the gap into the cylinder.
Piston Rings: Worn or damaged piston rings will cause blow-by resulting in blue/gray smoke.
Worn Cylinder Walls: Worn cylinder walls cause blow-by resulting in blue/gray smoke.
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Black Smoke: Black exhaust smoke is an indication of rich fuel condition. These are possible causes:
Fuel Injectors: A leaking or dripping fuel injector will cause a rich fuel condition.
Fuel Pressure Regulator: A stuck closed fuel pressure regulator will cause a rich fuel condition.
Fuel Return: A restricted fuel return line will cause a rich fuel condition.
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White/Gray Smoke: White exhaust smoke is an indication that coolant is burning in the combustion chamber. These are possible causes:
Cylinder Head: A crack in the cylinder head (around the coolant jacket) will cause coolant to enter the combustion chamber.
Engine Block: A crack in the deck of an engine block near the coolant jacket will cause coolant to enter the combustion chamber.
Head Gasket: A damaged or blown head gasket will cause coolant to enter the combustion chamber resulting in white/gray smoke coming from the tailpipe.
by ASE Study Guide
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