Horrible stumble & knock.

[firelama]

I have an 86 GN that has developed a serious tip-in stumble along with horrible knock at WOT. These symtoms manifested after I installed the billet roller camshaft. I have swapped out Coil pack, IAC, Both Temp sensors, Plugs (gapped at .035), Plug wires, ECM (with identical hartline chip), Cam sensor, Crank position sensor, O2 Sensor,

I recorded a quick run with direct scan. If anybody wants to review the run here is the link to the saved DS file.
http://gitflorida.com/RUN.2


List of Mods to the car include.
PT52, MSD 50lbs Injectors, Champion Iron Heads, Hartline Chip, Adjustable FP, Walboro 340, Billet Roller Cam,

 

[camino70]

I would triple check the cam sensor position first.


Ron

 

[firelama]

I just checked my cam sensor following the instructions I got with my cam tool and the car still has the same symptoms.

 

[firelama]

Swapped in a LS1 Maf and Translator with the Base and WOT settings set to the defaults and the Tip in stumble is gone along with the knock. But now the car wants to create over 20lbs of boost.

 

[camino70]

I am not sure, but I think the chip plays a part with boost levels in conjunction with the wastegate(if you changed the chip with the translator). Either way, try turning the boost down with the wastegate.

Ron