Car stops running after driving

Hello. I have a 3.0 V6 93 labaron about 150,000 miles. I have had issues with cooling and have replaced the water pump. Took me some time to set the timing too. But I have been driving about 2 months all was fine. Now it seems I must let the car cool off severl hours to drive again.
It almost sounds like the car is not getting or running out of gas, yet Im using fuel like crazy. There is some popping like fuel is getting to exaust. Did key on key off. No codes. I get a 12 and 55. Injectors seem to be working. I do notice lower than normal oil pressure when its running like this. Car does seem to be running hot, but not to the point of overheating. On cooler days, seems to run fine. It wasnt till this hot weather it started stalling after driving for 20-30 mins. It must be heat related, so its hard to rule things out. I keep thinking sensor? But never get any codes. Also not sure if its normal, but a strong vacume is heard through (ecu) via air cleaner housing. Any help would be appreciated. Thanks update I just did a compression check, when I was having the issue. I got 180 on every cylinder except #4 which repeatedly reads 160-165.