Cold engine knock,what oil should I use?

[Mike_dup1]

The engine noise does not bother me anymore, like I said I know of several who have close to or over 100,000 miles on the 1999 and 2000 5.3L with the noise there all along and they have had no engine problems. There is nothing you can do to stop the carbon from forming. I have run almost gallons of PI thru it over the last 10,000 miles but that does not seem to make any difference with this noise. The emissions programs these engines run are the reason for the carbon. I have a relative with a 2001 Lumina that is driving the Chevy dealer nuts. She only drives it around town to Walmart, church etc and about every 6 months they have to clean out the whole fuel system. It gets so carboned up, I have never in 40 yrs of driving seen anything like it.

The 4.3L engine is not immune to carbon.

Mike

1992 Chevy 4x4 5.0L 75,000 miles
1993 Lumina 3.1 sedan 61,000 miles
2001 GMC SLT Ext. Cab Z71 39,000 miles
2002 Trans Am WS6 LS1 5.7L 13,000 miles

[ October 24, 2003, 07:04 AM: Message edited by: Mike ]

 

[dickwells]

Maybe the Lumina relative should try another brand of gas. We know there are tendencies for carboning but not all of these cars do it. I have had 350/305 trucks since 73 and never had one make a "carbon" knock or piston slap. Since the 4.3 is the same engine, it may not be immune to carbon but it has a better chance than something with the fast quenching aluminum heads that cause the carbon to deposit in them.

 

[sub_zero]

quote:

---

Originally posted by Mike:

I have heard the noise and if its pistons, why do you hear a knock noise about 1-3 times a second when the piston is moving some 70 time per seconds? 5.7L LS1

---

Don't forget it is a four stroke and not all the pistons are slapping, only the normal ones