I have a 4.0 from a 92 wrangler swapped into my CJ. Went wheeling at Wheelin' 4 Hope this weekend in Arrington, VA. On the way up the jeep sputtered and stalled many times on the highway. Each time, I opened the hood and waited about 10 minutes and the jeep fired up and ran normal. Replaced fuel filter, battery and coil but the problem persisted. Only seems to happen in hot weather. I also have an 8274 so there's not a lot of air flow. Could this be the heat soak/vapor lock issue that affects some 4.0s? If so, what's a good fix (I only see fixes for later model - OBD2 - 4.0s). Also, I don't have a fan shroud but plan to put one on now. Any other thoughts, ideas or advice? I hate being 'that guy' with the jeep that keeps breaking down.