I have a Mitsubishi with 146k miles on it. A year ago it started a strange knock upon starting it. Its a fairly loud knock. If I leave it knock for about 5 seconds and turn it off/restart it, the knock will disappears. It happens in summer and winter. It never happens once the car is warmed up. If I leave it knock, the sound will gradually fade and disappear as the car warms up. It seems to be loudest on the right side of the engine (drive belts side). She has new belts installed, new timing belt and hyd tensioner pulley, new water pump, spark plugs, ignition wires and distrib cap/button.
Carlos
Could be a sticky hydraulic valve lifter.
Are you using the recommended oil viscosity?
That’s what I thought too (others said that as a possibility), but on second thought…it’s kinda too loud to be a lifter I think. It if is that, is there a way to troubleshoot and find the one?..is there an indication on the valve that is sticking that can be identified by pulling the valve cover?
If you rev it a little does the knock rate change with engine speed?
Yes, the freq. of the knock increases…and the sound diminishes a bit as I get up to over 2000 rpm. …then it sounds the same once the rpms drop back down.
Thanks for asking…
Get the oil pressure measured with a gauge.
You might want to get a couple of rod bearings inspected on the right hand cylinders. That’s a pricey test though.
This is the 3l V6, yes?
Yeah, it’s a 3.0L V6. What do you think it’s a rod bearings? What is it about these bearings that suddenly make them stop making the noise on the 2nd start…even while the engine is still cold.
C
Since I haven’t heard the sound I can only make guesses.
Did you ever find a resolution to this issue? I am having the same issue with my 2001 Eclipse GT and it started around the same mileage, 145K. I cannot figure it out it goes away completely then a month later it’s back!!