What to do about a loud cold start knock?
What to do about a loud cold start knock?
Running SeaFoam through the oil 50-110 miles before and oil change cleans out the oil and really helps to stop the tick/knock. My 96 had this last month and the tick would last about a min and then stop. All vehicles with Hydraulic lifters can have this happen.
What was the loud cold start knock that went away?
A few months ago my nephew went to a quick oil change place and they talked him into a “engine cleaning”. They added it to his oil, ran it for 15 minutes, drained the oil, changed the filter and refilled with oil. On his way home, the truck with 101,000 miles on it threw a rod, popped it right out of the side of the block.
Where does the morning sickness knock come from?
The morning sickness knock can come from two areas (assuming engine wear is normal for the mileage), the lifters and piston slap (as has been suggested). Neither one will hurt the engine, just piss off the owner.
What does knocking noise at start up mean?
Noise did not occur after sitting overnight. Noise duration is too short to track down. Noise is closer to a light tapping, definitely not a heavy thump. Similar to an exhaust manifold leak, but not as loud. Noise does not happen every time. More likely to occur after the truck has been sitting a few days. Ed B. cigroller July 6, 2016, 2:18am #7
What causes a loud cold start knock noise?
I don’t think there is anything (maybe a rebuild) that will fix the piston slap. The lifter noise is usually dirt and, or wear, that lets the lifter “bleed down”. Sometimes as @ Conlan Rose suggested, it might be a slow to build oil pressure issue, that is caused by a dirty oil filter, sometimes it’s clogged oil passages.
When does the loud cold start knock go away?
It’s loud enough to have given me pause but it’s gone in 20-30 seconds as oil gets to moving around and the vehicle commences its warm-up. Doing some reading, online, it appears that this is ‘normal’ for 5.3L Vortecs and that it isn’t harmful.
Why does my Blazer make a knocking noise when I start it up?
2000 Blazer 4wd, automatic, 122000 miles In the last couple of weeks, if the Blazer isn’t driven for 3 or more days, there is a slight knocking noise for 15 to 20 seconds after start up. Oil level and pressure are fine. I’m guessing it’s the lifters, but I’m open to any suggestions.
