alrigh so recently my car has been running like shit and some days it would be fine, when ever i get to a stop light it would idle fine then cut off or even when i let it idle for a bit, when i start it again its starts to jump and and stall, start it again have to play with the gas and it drives ok, it use to back fire like crazy but not so much anymore, so it has its days so far ive changed, tps sensor, fuel filter, fuel pump, distributor cap, roter, ignition wires also cleant up the spark plugs which i got couple of months back and stilll the same, any advice or has anyone gone through the same prob that can help me fix it? thanks
this could be a lot of things what do you mean you start it up and it starts to jump? if your car is moving on you at all when you start it could be your clutch or clutch system. it could be still engaged at idle.
If its misfiring that could be injectors or your coil. you could have a few that are going. When an injector starts to go it will work sometimes then it will randomly stop then it will work and stop. check your continuity with a volt meter. on the plugs. your meeter should read 0 if they are good.
look for vacuum leaks
If you’ve checked ur spark and its all good. Check ur injectors. check for the resistance.
If the injectors and good and ignition system is good. Check ur remaining sensors.
Maf sensor, coolant temp sensor, shit like that.
These engines can be had for cheap, so the sensors and spare parts can be had for even cheaper.
I would also check your ecu . pull it out undo those 4 screws on the ecu plate and check to see if it is corroded any where. It seems rather common for s13’s (assuming you have one) to let water into the fuel control unit of the ecu and you end up back firing and running like shit, this is also assuming your ka is stock if your boosted it could be many different problems.
The 2 times I had a problem with my KA it was a bad injector and the other time the o2 sensor, take a look at those. the symptoms were somewhat similar to yours.
buy my drivetrain. runs like a champ 
out of 96 240 ka 5spd comes with used rad and short air also a ecu $300 bro!!!
so what was the problems answer i demand to know since you put it in the wrong section.
Clean your maf?
This thread is full of shit…
KA’s dont actually have problems.
jk.