I have a 99 Chevy Silverado 5.3 .When it is cold it will crank fine but when it sits for ten too twenty minutes it’s hard to crankRelated Questions1999 Chevy Silverado 5.3 litertrans started shifting hard and check engine soon light came on today1999 Chevy Silverado 1500 ext cab 5.3 V8How imperative is it to change the spark plugs and wire at 100K miles. Truck is running fine and has 127K miles on it. Will be driving about 1800 miles pulling a 3500lb max load trailer1999 Chevy Silverado 2500Cannot get the air to move between the different setting. Defrost to floor. Stuck in between and not much air coming out.