Hey guys, i have been having some issues with my old lancer and after some attempts to resolve i still have no idea what the problem is.

Problem: Stalling/Poor idle when cold, when hot idle is smoother but not perfect and you can feel roughness. When revving in Park the revs hit 2k then drop to 1k continuously (so up down up down, etc.). When revving higher it is fine, when in all other gears the car drives however roughness in the engine is felt (by roughness i mean excessive vibration, sputtering, etc).

So far i have cleaned the throttle body, checked vac hoses for leaks, checked spark plugs & leads and tested the emissions computer (forget the name of it) with a voltmeter. None of these were in disrepairs. I will be swapping the plugs, leads and air filter in the hopes that solves it. Although i really am stumped.

The car also has the Check Engine light triggered, i am not sure if this would make it go into limp mode? It definitely doesnt drive limp at all! Except for the issues... Again, after testing that computer with a voltmeter i was getting 'engine ok' readings.

Any ideas would be much appreciated! Thanks in advance

do they have a MAP sensor? if they do id be looking at that, it might have died.

do they have a MAP sensor? if they do id be looking at that, it might have died.

That the same as the MAF? I disconnected that and the car ran even worse, so i presume it is working. Is it one of those things that either works or doesnt or can it deteriorate and slowly affect the running of the engine?

yeah MAP sensor stands for Manifold Air Pressure sensor. theres usually a small plug and a small vacuum hose running into them.