2003 Suburban problem
 

I have a very nice, low miles (98000) suburban with the 5.3 engine. this vehicle runs very well, is very comfortable, and gets reasonable gas mileage. One big problem: when the outside temperature is over 80 degrees, this vehicle will at times randomly die. No codes, no notice, just die. When I roll it to a stop, it will restart and may run for a while or may die again. This never happens when the temp is cooler. Needless to say in heavy traffic is very unsafe. I have had several GM mechanics try to replicate the problem to no avail. I have drove this vehicle non stop in cooler weather for over 600 miles with no issues. Once drove 380 miles to a city and in stop and go traffic at 88 degrees it died, and continued to die several times til I found a place to park. Then drove 380 miles back home and no problems, as temp was a high of 78. I am at wits end. Really want to use this vehicle in the summer, not just a winter ride. Any suggestions?

If it was my 93 I would replace the ignition module in the distributor. Don't know if that applies to your year