Hey folks.
A friend of mine has a 2000 Acura Integra GSR. It has the B18C engine (1.8L 4cyl VTEC). Last summer he installed a turbocharger on the engine. He knew the engine was kind of tired (it smoked a little bit on acceleration), so he didn't boost a whole lot (3psi, iirc). He also ran it a little rich to keep from burning it up. Well, eventually it started to smoke a lot, and he pulled the engine when it got real bad. (He's building a brand new one for the car as we type).
What is interesting, is that 3 of the 4 cylinders look relatively normal. There is some black carbon buildup on the valves and piston heads, likely from running rich. However, cylinder #3 is spartan clean- everything in it looks like shiny new metal. And of course, #3 is the cylinder where all the smoke was coming from- a small section of the piston (about 1") is melted... on the intake side.
Any thoughts as to why just one piston would melt, and why that one cylinder would be clean? We were thinking maybe a failed injector, but the car wasn't missing or detonating at all. It ran with full smooth power all the way up until the engine was pulled. Also, if the piston was going to melt, why on the intake side and not the exhaust side?
Thanks for any insight on the mystery.
-ph