i have a 87’ gmc s-15 and i noticed about for 2 months now everymorning i start the truck a white-ish like puff of smoke comes out of the exaust. this only happens in the morning and doesnt do it again until the next morning. what could be causing this? and is it expensive to repair?
Need to know what color smoke but…a slight leak from something like valve stem seals or even a mini leak in a head gasket. The leak accumulates over night then burns off at start up. On a truck this age it could be anything but someone can start by learning the smoke color…white = antifreeze…black = oil, then go from there. Valve stem seal repair will be much less than a head gasket and until it affects the running of the engine ( ie. smoking all the time ) you can elect to just live with it while at the same time gettinig it diagnosed and saving ahead for a possible repair.
THANKS ALOT B’CUS I LOVE THIS TRUCK AND PLAN TO KEEP IT ANOTHER 10YEARS!! BUT THE SMOKE IS DEFINITELY LIKE HAZY WHITE AND THE TRUCK RUNS FINE AND STARTS EVERYDAY EVEN IN THE WINTER @ -45, SHE STARTS WITH A FEW CRANKS
…and keep tabs on your fluid levels and condition. When you check the oil level, also look at the appearance of the oil on the stick. If it’s getting antifreeze in it, it will be a bit milky and it’s time to get repairs. If it looks like normal oil, no hurry to get repairs. Check your antifreeze in the radiator ( not in the rez ), if it has blobs of something it’s probably oil and needs repairs.
If the smoke smells like fuel, the fuel injectors could be leaking, during engine shut-down, into the cylinders. Upon start, the fuel is vaporized, expelled out the tail pipe. Anybody want to take a sniff; or, stand at the tail pipe, with a lit propane torch, during engine start?