Problem

My friend owns a 91 mr2 non turbo. it hasnt ran for like 4months, when u start it and let it idle it revs up to 2000 then drops to 1000 then back up this continues, is this an o2 sensor because it acts like its tryin to warm up, like the computer thinks its winter? Idk can ne one help me?


I appricitae it thanx

99% of t he imte, whe nyou have bouncing idel at start up, it the coolant. I have the coolant properly flushed and filled .... as per the instructions for doing this in an MR2.

Chances are there is just air in the system.