3406E warms up looses boost ?

[Bengy88]

Your truck wouldn’t happen to have one of the resistors that plug into the fuel temp sensor and boost pressure sensor to fool the ecm into over fueling your truck would it? If so throw them in the trash asap, I can’t throw the name of the company that makes them out here but I’ve seen a lot of performance issues out of trucks with them on cats. Also has the truck ever been tuned? A lot of guys will throw a tune in these engines that you can get for free from other forums and 80% of them are complete trash. Rawze is 100% correct. Low egt’s are just as bad as high egt’s. if you want you can pm me your contact information and I’ll help walk you through some things.