Thanks to C5-TECH's post on the other forum:
http://forums.corvetteforum.com/zerothread?id=503676
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Engine Knock on Startup (including Hot Re-Starts) on LS1 V8 Engine #PI00150 - (02/12/2003)
Engine Knock on Startup (including Hot Re-starts) on LS1 V8 Engine
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When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.
Condition/Concern:
Engine knock on startup (including hot re-starts) on LS1 V8 engines built after April of 2001
Recommendation/Instructions:
Determine if a piston is making the noise by shorting out the fuel injectors to individual cylinders. After determining which cylinders are the source of the knock noise (90% of the time it should be #1) eight standard size pistons may be ordered through SPO.
These pistons should be measured with the largest piston going in the noisy bore, and the next largest going into #1 bore and #8 bore, in that order. If measuring equipment is unavailable, most machine shops should have the capability of determining piston size.
The new piston will come with rings, but they are not to be used. The rings should be removed from the old piston, and install on new piston in the position they were removed to prevent oil consumption. Do NOT dress the bores! Care should be taken to assure the old rings are re-installed in the same position in the same bores as they came out of. Document ID 195097 describes the piston and connecting rod assemble procedure which requires the use of heat during dis-assembly and re-assembly. HEAT MUST BE USED DURING DIS- ASSEMBLY AND RE- ASSEMBLY TO PREVENT PISTON DAMAGE and/or rod distortion.
Linear Mode
