LT4 Hotcam 5.7 Issues - Freshly Built

[Dlipp_]

Just recently got my truck running after doing the LT4 hot cam. Here’s all I did to it

LT4 Hotcam
LS6 Springs
787 retainers with the 648 locks
Stock 1.5 rockers
Melling stock push rods
New lifters
Screw in rocker studs
Valve seals
Stainless, undercut & swirl polished exhaust valves
New standard motor parts MPFI conversion injection
New 180 thermostat
New rocker balls and nuts
New Cloyes Timing set, holly aluminum cover
PCM tuned for everything I did from Black Bear Performance.

put the cam in and lined the dots up at TDC, set the lash to zero and then 3/4 turn.

Here’s the issues I’m having, got everything ready, started the truck, fired right up.. idles high around 1000.. makes some valve train noise, I think.. or sounds like the new power steering pump… but I started getting a cyl 6 misfire code, put a new plug in and now I’m getting multiple random misfire code. At 1000rpm it’s idling at, it doesn’t sound like it’s misfire or popping. And when I hit the throttle it doesn’t really want to rev right up, kind of have to give it to it lol or work it up.

Anyone know why? Valves out of adjustment? Really hoping it’s not the new fuel injection.

 

[L31MaxExpress]

In my experience the misfire detection will need to be dumbed down some under ~1,200 rpm with that cam or it will set a P0300.

Lash the valves with it running, then verify it does not have a vacuum leak(s).

Having tuned a few of these, should start and run on the stock tune but they really wake up with correct tuning.

 

[Dlipp_]

In my experience the misfire detection will need to be dumbed down some under ~1,200 rpm with that cam or it will set a P0300.

Lash the valves with it running, then verify it does not have a vacuum leak(s).

Having tuned a few of these, should start and run on the stock tune but they really wake up with correct tuning.

Thanks for the input, I actually figured it out.. prong inside the plug for the fuel injection was bent, no misfire code now, once up to temp, idles around 800