1994 GMC Sierra stalls out while driving and in park.
1994 GMC Sierra stalls out while driving and in park. Doesn't want to
accelerate and getting poor gas mileage. Already changed spark plugs, spark
plug wires, fuel filter
Not sure if this is related but also losing a lot of coolant, but can't find a leak
Sounds like you may have a possible bad head gasket. You would have noticed a lot of white exhaust out the the tail pipe, and would notice an coolant smell. Need to figure out if loosing anti-freeze is the cause of the way the engine is acting. Also check to see if the oil is over full, coolant can seep into the engine oil.
Did you check for a vacuum leak?
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