[jafowler49]

When I slow down or come to a stop, or when it is idling about 500 RPM, the car jerks bad, and I either have to come to a stop quickly and probably kick it in neutral and give it gas, or keep it moving steady at about 1000 RPM, or else it usually dies.
It does this after about 20 minutes of driving, or maybe when the spark turns on or whatever.

I replaced fuel pump, ignition coil, ignition module.... No error codes are coming up, so probably not a sensor, and maybe not the ECM, yet still think this may be the problem... The car reads low voltage, so I was told by the mechanic that its either coil or bad ECM, but I changed coil, so we think its ECM.
Is there anyway I can check my coil, just in case, at home???
What are symptoms of bad ecm??
It did this a while back, and thats when it was the ignition coil, but it seems to be doing it again but worse... Any help appreciated....