Coolant leak and random rough idle
estone4009
12-23-2003, 05:53 PM
1999 Silverado 5.3 L
After driving for 3 or 4 days the coolant leaks down to a particular level in the tank. No signs of coolant anywhere in engine compartment and none on ground, oil, etc. I have had a pressure test done on the coolant system and it holds pressure. Does not overheat and leaks down to a particular place on the tank everytime. Where should I check to see where the coolant is going? When I pull the spark plugs what exactly should all of them look like? The truck will randomly have a spurt of rough idiling that can't be traced down. The computer will randomly throw a P171 which is lean left bank on the exhaust sensor. Fuel pump and fuel regulator just replaced. Any ideas would help. Thanks.
After driving for 3 or 4 days the coolant leaks down to a particular level in the tank. No signs of coolant anywhere in engine compartment and none on ground, oil, etc. I have had a pressure test done on the coolant system and it holds pressure. Does not overheat and leaks down to a particular place on the tank everytime. Where should I check to see where the coolant is going? When I pull the spark plugs what exactly should all of them look like? The truck will randomly have a spurt of rough idiling that can't be traced down. The computer will randomly throw a P171 which is lean left bank on the exhaust sensor. Fuel pump and fuel regulator just replaced. Any ideas would help. Thanks.
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