reactor2

I just started my vehicle for the first time this year and I noticed an occasional/random "ting" sound at idle RPM. I don't know if it did this before or if this is something new. I threw the scanner on it and noticed that #3 is getting a fair amount of misfires (more than any other cylinder - with the most notable activity coming from 1 and 3. However, at > 2500 rpm the misfire counts across all cylinders is 0 (which probably explains why my converter won't stay locked when < 2500 rpm). However, when holding the RPM at 2500+ rpm it isn't smooth. That is, in neutral it still has a noticeable stumble (diminishing with RPM but still noticeable). What is "normal" for a modified engine and what should I look for? BTW. This is nothing new, it has always run like this after the mods (several years) and remains the same even with plug and coil changes.

*I don't think any misfire codes have ever been thrown

Main Engine Mods:
228/232 .571/.573 112
Dart Pro 1 205 heads
Fast Intake, LS2 TB
NGK Iridium gapped at ~.035"
GMPP Red Wires
MSD Coils (new version) - same behavior with stock coils.
YellaTerra rocker arms
BBK Headers
P1SC - 4.25" (6-7psi)

MAF and VE tables dialed in pretty good (LTFT < 3% all RPMs and ~1.5 at idle rpms).

enoniam

It doesn't sound normal to me, especially at well above idle rpms.

tblu92

When installing many mods such as cams LT headers or a stall converter---you will get "FALSE MISFIRES " -----A false misfire will keep your converter from locking---
A common fix is to alter the misfire tables to get rid of the false misfires--
Go to engine diagnostics and simply MAX out all the misfire tables----this will eliminate all the false misfires and the TCC will work normally------But you must be sure that in fact you have no real misfire--If you do--then you have to fix the misfire problem