I drive an Australian 1986 4Runner, 4Y Engine, carby, 2.2L engine, 5 gears manual. 215.000km
The car runs, it always starts up and drives. However, there are some problems which occur randomly, on some days you barely take notice of it, on other days it starts making trouble right after the start.
1. Low power - I dont expect much from 97hp, but when I reach any kind of inlcines it rapidly looses power, and speed (In a way that I am obstructing the traffic). Fells like it has no power in the lower revs.
2. Stuttering - The car idles well, but sometimes (looks like this happens only in higher gears, 4&5 gear) the engine just fails for about half a second, meaning the car looses all acceleration power. However, this is just very short and the engine runs smooth like before after that.
3. Misfiring - I get random misfires, sounds like driving over a plastic bottle. This happens mostly when the car is rolling down a hill and runs with the accelerator pedal only barely pressed down.
I also noticed misfires when the stuttering happens, but it is hard to hear it while driving.
It also happened once to me, that the idle was very very rough, just keeping the engine running. This ocurred right after starting the engine up. I had to be very slow with the clutch, but the car drove at all. After about 7mins driving I parked the car, went shopping.
15mins later, same again...very rough idle. I dont know how to explain this, ok: I went to the exhaust and held my hand in front of it. It was not like a constant pressure coming from it, more like bursts. After 1min idling the revs went back to normal, without me doing anything.
Also, the car is pretty smelly sometimes, exhaust fumes. Today I started the car, drove 2-3ks trough the city and stopped at a red light. When I accelerated, the engine "choked", not accelerating at all when I pressed the accelerator pedal. Then it spinned up without problems and the next stops were fine.
It is strange, only happens sometimes.
The previous owner gave the car to a mechanic and he replaced the ignition points, adjusted the dwell angle and ignition timing...Also adjusted the carby idle mixture and speed. Fuel pump and spark plugs have been replaced recently aswell.
Today I checked the distributor cap and found this:

Why is the cap scratched like this? The contacts look bad, too. The rotor is tight, not wobbling around. Strange...
I also checked all four spark plugs:

They all look like this one, what do you say? Is it too white? I found a white "crusty" substance on the outside(!) of all plugs, looks like lime/chalk. I cant explain what this is, as the plugs should be new and sealed by the spark plug connector?

Hope you have some ideas on what to do! Heres a pic of the whole engine:
