Just wondering what is causing this misfire. BTW, I have seen this happen on 05 5.3/6.0 cammed engines. Furthermore it only happens at about 6600+ RPM's. I have never seen this happen on any other year but the 05 year model year. Anybody else encounter this issue?
could be hitting the rev limiter?
Sulski Performance Tuning
2000 WS6 M6 - LS6 (long block, refreshed top end), 10.8:1 CR, 90 mm ported FAST, Exo-Skel, 227/232 cam, QTP HVMC, EWP, GMMG, 9" w/4.11s
2018 Sierra SLT 5.3L A8 - Airaid intake tube, GM Borla catback, L86 Intake/Ported TB
No.. I made sure the rev limiter is well above the shift point.Originally Posted by WS6FirebirdTA00
Maybe something like the dynamic airflow filtering,
being slow to pull back when RPMs drop fast? Then
you might be way overfueled for a brief period?
If you scatter-plot the DynAir vs RPM in a spreadsheet
program (Excel or freeware) do you see that it breaks
one way on the up-slope and another on the down?
Figure maybe MAP is dropping fast at the same time
and maybe the computation (as-filtered) is just slower
than the reality of airflow?
Plug gap maybe? Just a guess here...
Does the `05 have different coils than previous model year trucks?
Always Support Our Troops!
+Plug gap maybe? Just a guess here...
Does the `05 have different coils than previous model year trucks?
Tried different plugs/wires with different gaps and does not seem to fix the problem. I have not checked if the coals are different for 05's.
I should have made myself clearer. This happens when the RPM is still climibing and not when the RPM is dropping.
I just remembered that I loose connection from the PCM with the HPT scanner when this happens and have no trouble connecting again.
Anybody else wants to give this a shot?
I'd be checking grounds. If your loosing communication, then the PCM is shutting off momentarily.
Tim
GM World Class TechnicianASE Master Auto TechnicianL1 Certification2001 Silverado 6.0L Swap
Reply With Quote
