5.3L 02 Tahoe Engine cold start - sounds like it's coming apart!!
02-03-2010, 09:06 PM
#1
Melting Slicks
Thread Starter
5.3L 02 Tahoe Engine cold start - sounds like it's coming apart!!
I've got an 02 Tahoe I bought new and now only has 52k on the clock (low miles, ey?
)
After it has been sitting around a few days in the cold (30's-40's) on start up it quite literally sounds like the engine is about to come apart. A HORRIBLE knocking noise and mixed in with that can clearly hear a couple of lifters clicking like crazy. There is no smoke coming out exhaust, oil level is fine, and correct SAE 5w-30 Pennzoil has been used since new and always changed when the DIC light comes on, usually around 4000 miles or so.
Oil pressure comes right up to 40 then with increase in RPM, up to as high as 60-70 psi. It's so bad, I almost feel like I need to turn it off...but after a couple of minutes (not seconds) it settles down and sounds fine. I've done the Seafoam direct to intake, before last oil change I ran some Rislone for about 50 miles, then changed the oil. All to no avial.
I know this is NOT right..something has to be wrong somewhere. BUT...Doing a Google search I come up with the following from GM
Info - Engine Knock on Cold Start #01-06-01-028A - (Mar 18, 2003)
Engine Knock on Cold Start
1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (SUV)
with 4.8L, 5.3L or 6.0L Engine (VINs V, T, Z, U -- RPOs LR4, LM7, L59, LQ4)
This bulletin is being revised to add an additional engine to the models section. Please discard Corporate Bulletin Number 01-06-01-028 (Section 06-Engine).
Some of the above vehicles may exhibit an engine knock noise that begins in the first 19,000-24,000 km (12,000-15,000 mi) of use. The knock noise is most often noticed during initial start-up and typically disappears within the first 5-30 seconds (may last longer in extreme cold temperatures). The noise is usually more noticeable on the initial start-up when the temperature is below 10°C (50°F) and may be more pronounced on the first cold start following a long trip.
This noise may be caused by an interaction between carbon that has formed on the piston, the piston motion and the cylinder wall. GM Powertrain Engineering, and an analysis of engines with this condition, has confirmed that the noise is not detrimental to the performance, reliability or durability of the engine. THIS NOISE DOES NOT HAVE ANY EFFECT ON THE LONGEVITY OF ANY OF THE ENGINE COMPONENTS
WHAT? Engine parts banging around inside the block don't do any damage?
I'm all ears to hear someone comment on this...
)After it has been sitting around a few days in the cold (30's-40's) on start up it quite literally sounds like the engine is about to come apart. A HORRIBLE knocking noise and mixed in with that can clearly hear a couple of lifters clicking like crazy. There is no smoke coming out exhaust, oil level is fine, and correct SAE 5w-30 Pennzoil has been used since new and always changed when the DIC light comes on, usually around 4000 miles or so.
Oil pressure comes right up to 40 then with increase in RPM, up to as high as 60-70 psi. It's so bad, I almost feel like I need to turn it off...but after a couple of minutes (not seconds) it settles down and sounds fine. I've done the Seafoam direct to intake, before last oil change I ran some Rislone for about 50 miles, then changed the oil. All to no avial.
I know this is NOT right..something has to be wrong somewhere. BUT...Doing a Google search I come up with the following from GM
Info - Engine Knock on Cold Start #01-06-01-028A - (Mar 18, 2003)
Engine Knock on Cold Start
1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (SUV)
with 4.8L, 5.3L or 6.0L Engine (VINs V, T, Z, U -- RPOs LR4, LM7, L59, LQ4)
This bulletin is being revised to add an additional engine to the models section. Please discard Corporate Bulletin Number 01-06-01-028 (Section 06-Engine).
Some of the above vehicles may exhibit an engine knock noise that begins in the first 19,000-24,000 km (12,000-15,000 mi) of use. The knock noise is most often noticed during initial start-up and typically disappears within the first 5-30 seconds (may last longer in extreme cold temperatures). The noise is usually more noticeable on the initial start-up when the temperature is below 10°C (50°F) and may be more pronounced on the first cold start following a long trip.
This noise may be caused by an interaction between carbon that has formed on the piston, the piston motion and the cylinder wall. GM Powertrain Engineering, and an analysis of engines with this condition, has confirmed that the noise is not detrimental to the performance, reliability or durability of the engine. THIS NOISE DOES NOT HAVE ANY EFFECT ON THE LONGEVITY OF ANY OF THE ENGINE COMPONENTS
WHAT? Engine parts banging around inside the block don't do any damage?
I'm all ears to hear someone comment on this...
