Hi all, truck has a stalling probelm after running for 45 minutes, when ever I come to a stop the motor stops running. I had the truck into the dealer for two days. It is not showing any codes. The fuel press is fine. Everything is ready fine off the computer. They thought it was maybe bad grounds so they cleaned them and thought it was fixed. 12 miles away it died again. I replaces the IAC and cleaned the TB . And it still dieing after running 30-45 minutes when I come to a stop. Any idea?

 

Look for a leak around the exhaust manifold, will sometimes trip an O2 sensor but often will not generate a CEL and will cause a drop in RPMs and a stall at stops or when shifting from forward to reverse sometimes. I've seen where it doesn't do it cold because the truck is still in open loop, but as soon as it's up to full temp and begins taking readings from all the sensors & enters closed loop, it begins to drop RPM and stall...