my car did the same thing, if i apply brake slowly for a light, it'll just stall, sometimes it stalls on a freeway offram (imagen that, you are going off the freeway at a speed too fast for your own good, and than your engine dies, giving out power steering and power brakes....), i've found my struggle to be the ICV, i've made my own intake, and it wasn't doing very good, i switched to AEM (for the carb#) and now it runs fine.
so if you have an after market intake, check on all the hoses make sure they are correcly connected, and that there's no sevear bends on the rubber tubing causing a restricted air flow.
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