loss of power
 

Buddy s got a 99 with new inj. pump and lift pump and when he pulls a small trailer he cant get over 55 and said its real slug like. what could this be

whats the boost doing? any mods? what tranny does he got also? thanks!

all stock and turbo sounds good

was it doing this before the new IP and LP?

what lift pump was put back in? if it's stock it could already be toast. his injectors could also be on the way out

thats what im thinkin injectors

I'd check fuel pressure between LP and IP first

or possibly map sensor needs replaced? i got my truck and it had new ip and lp. 194000 miles. week later map sensor went out. 60 bucks and i was rollin good again.