I used a synthetic oil this time, always use regular. Maybe broke a seal or moved some debris??? Or could it be something else. Awful noise like rattling when it first wouldnt start, it almost started but prior attempts just a little chugging no start.
My car has 220000 miles.
My car has an automatic transmission.
Hello - it is possible that the engine "jumped time" because of the momentary loss of oil pressure after the oil change. (The fact that you changed to synthetic oil does not come into play here.) The timing chain tensioners utilize engine oil pressure for part of their tension, and a high-mileage engine like yours would likely have a worn (stretched) timing chain and weak tensioners. If there are any problem codes set, turning on the Check Engine light, these codes would be highly instructive. I would recommend having a Car Is Not Starting Inspection completed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
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