Hello,
My A/T mini is suffering a serious problem after engine/gearbox-rebuilding by an unskilled mechanic.
The symptom is that the automatic transmission is working well in idle time, but when the engine is hot, I can hear terrible gear grinding sound.
( I guess it is the non-matching of the gears)
I googled the problem can happen when the oil pressure is low, so that I've checked the oil pressure with pressure guage.
When cold, it's okay, but hot, It dropped (I think due to viscosity on temperature) and the gear is non-matching still for the warmed engine
What can be the problem?
- oil pump?
- oil pressure switch?
- oil relief valve?
- and another?
My guess is as follows:
- oil pump would be okay, because the pressure is normal in idle.
- oil pressure switch: I'm not sure that it controls the oil pressure electrically. I think the switch is just showing warning light. Am I right?
- oil relief valve: the spring tension is weak when oil temperature rises.
But that's my guess just without certainty.
Please help me!
Thank you in advance
SJ
Edited by miniminiman, 21 July 2017 - 07:04 PM.