I have an '84 240 dl wagon, and I think I have a relativley unique problem. I have a rpm and enine spike during idle and while accelerating. When the rpms spike (usually from 2000 to about 5000 at the highest), the engine never really reaches what the rpms read. So this tells me that it's an electrical problem. Now, sometimes the idle spiking goes away, but the acceleration spike never does. I have tested and cleaned the air control valve, the tps, and the connections to the icm, tested for continuity on the supply circuit to the coil, and checked all grounds. The only time something seems to change is when I mess with the icm. From what I understand so far, the icm either works, or it doesn't. What I don't understand is why this is so difficult to find on a relativley simple set of circuits..... Could someone perhaps point me in the right direction, or give me something else to look for?