High Idle-Limp Mode-HELP!!
2008 6.4 bone stock. Everything was fine in the morning then this happened:
Started truck around lunch and idled up to about 1600 rpm. Turned truck off and hooked up scanner to obd port. No codes were thrown but the check engine wrench was still on the HUD. Cleared the wrench and truck idled back to normal drove on the freeway with no issues until I shut the truck off. Started back up and wrench was back along with the high idle. Found out that if I hit the brake it would idle down temporarily. Drove home in limp mode and it is parked now. Please help with any info if this sounds familiar to anyone. Thanks in advance.