21st Feb 2005, 22:14
Possible loose timing belt?
Noise under load is probably low octane fuel - mine will only use 89.
Always use thin oil in these engines, lighter than 10w30. They have a design flaw where the oil drain holes in the valve sleeves are too small, and the slow moving oil will leave the valves open, causing them to burn.
18th Mar 2005, 21:42
I've owned 4 of these little guys. It's a common noise as 1 cylinder is a different size than the others. This is for engine balance.
17th Dec 2005, 14:10
When I first bought a 1995 GEO it made a small piston noise when it was cold. As it warmed up the noise disappeared. As the car got older, when starting cold, the noise got a little noisier and lasted longer, but disappeared as it warmed up. I have about one hundred and twenty thousand km on the engine.
The timing belt, water pump and lifters have been changed. I tried using higher grade and then synthetic oil and the noise is still there until the engine is warm.
I was told it was the piston slap and that is the way the car is. The shop also told me that there is a new forged piston that would get rid of the noise.
I just do not want to see the connecting rods flying out the side of the block if I do nothing. Is the noise normal for the three cylinder engine? Is there something I should be doing to ensure the longest life for the car? I want to keep the car.