living in fear of car stalling out. I'm running out of Ideas

[smokey240sx]

I living in constant fear of my car stalling out. I went to numerous mechanics and they have found nothing wrong. One shop even let the car run for a few hour and it didn't stall out even once. Of course once I drove home it died on me. There are some warning sign to let me know when it will be happening. Horrible RPM stumbling, slow rev, and clanking sounds from the engine. If I let the car sit long enough all the problem seems to disappear. Its almost like the longer I let it sit the better it gets. I have replaced the plugs, wires, rotors, cap, MAF, battery, belts, cat, o2 sensor, vacuum lines, raise idle, clean AIV, checked EGR, I did compression, voltage, and vacuum tests. Everything is fixed and properly working. The only codes I pulled from the ECU were a lot of 55. I think once it gave me a fuel injector leak and another time crank angle sensor. I think it was just my eyes was playing trick because I've been staring at the code for few minutes. None of those codes showed up ever again. The first time this stalling out issue happened is when I got stuck in a snow bank. After an 1hr of waiting for help I got pissed off and started to rock myself out by flooring it then quickly throwing it in reverse. The clutch took a lot of beating but I had my son in the car. Please help me out. I can't do this anymore.......

[NISTECH]

When the car stalls out does it restart? There is a thread in here active right now going through most idle control valves. Try reading through it see if your problem is similar and give some of their tests and repairs a try. The thread is here in online mechanic.

[vancouverbc]

remove aiv and definitely clean the iaa unit. check all your grounds. from battery terminal to engine block should be less than 2 ohms. see recent thread by kirk on idle problems. there is link to online factory service manual.