2000, 454 vortec bb engine seems to be missing after distributor R&R

[Ttoyota]

Are you still getting the P0300? Or is that fixed too? I made a thread some time ago on my troubles after I did the 0411 swap. That's when my code popped up.

Here it is.

Yes, on the po300!! Thank you!! I'll read it. Christian definintly fixed my o2 issue and we were discussing the po300 deal. ThX. I'll read it now.

 

[Ttoyota]

How do you lose a big block? Have you tried looking under the hood?

Dang just figured out what you were referring too. That's funny. Read the title and it all came together... Ttyl

 

[Ttoyota]

Quick update. Ordered oem delco cap and rotor in hopes that the skip white distributor i installed is causing engine miss. Quick question, what are y'all setting your spark plug gaps at? .060 is standard but i know some of y'all are running them around .050. If so whats the logic behind that. Thanks for the help. The engine is 454 vortec thx. Won't be home for a bit to see if cap and rotor fixes missfire. I will update once completed.

 

[Mangonesailor]

Sorry I never got back to you on this. I tried .055 once, but had to end up putting all of my plugs at .050. The logic is that the resulting spark at such a gap and high RPM is not hot enough to start a large enough flame to completely burn all of the fuel in the chamber in time. Thus, you loose power through the exhaust and can cause a little spark knock as the cylinder temps will rise. This was actually dyno tested by an RV dealership somewhere since they had a bunch of 454's coming back with issues when loaded up going up hills. This solved that problem.

Did the cap/rotor solve your issues?

 

[Ttoyota]

No sir. I really don't get it. I swear it seems like the base tune from the 411 swap is the culprit. I can watch misfires count on all 8 gauges with the dongle/gauge pulled up and then if im driving while monitoring it one random cylinder will just start rappidly climbing until the cel flashes then it will go back down and all cylinders will just go threw the motions again. If i step on gas everything will drop to zero. But stay at a constant cruise speed and they will count up. If that makes any since. I dropped my plug gap back down to 50 it didn't help either. Took it to a shop for diagnosis. Bad decision money waisted claimed they cleaned bunch off computer and cps needed set. Nope i started said nothings changed. They said fp was good andall that. I really dont know. It starts perfect. Im instAlling a 300 amp ad244 alt. Upgrading grnds and leads. Hoping that might help. But it wont

 

[Christian Steffen]

No sir. I really don't get it. I swear it seems like the base tune from the 411 swap is the culprit. I can watch misfires count on all 8 gauges with the dongle/gauge pulled up and then if im driving while monitoring it one random cylinder will just start rappidly climbing until the cel flashes then it will go back down and all cylinders will just go threw the motions again. If i step on gas everything will drop to zero. But stay at a constant cruise speed and they will count up. If that makes any since. I dropped my plug gap back down to 50 it didn't help either. Took it to a shop for diagnosis. Bad decision money waisted claimed they cleaned bunch off computer and cps needed set. Nope i started said nothings changed. They said fp was good andall that. I really dont know. It starts perfect. Im instAlling a 300 amp ad244 alt. Upgrading grnds and leads. Hoping that might help. But it wont

I forget, can you actually feel any misfires?

 

[Ttoyota]

Yes i can hear a belch in the exhaust pipe. And i can feel it in my seat at idle. If im driving it seems perfectly fine. If i come to a stop light ill get that kick probably three seconds after idle. Nothing major but enough for a truck enthusist to know

 

[Mangonesailor]

Are there cylinders that seem to misfire more than the others? I get that all 8 are showing counts, but, lets say you graphed it... would there be 4 cylinders that tend to have more misfires than the rest? Can you post a screenshot of the cylinders with a bunch of misfire counts already? I'm curious as to which cylinders they are and where they are in the firing order and where they are on the engine.

I re-read your posts. So, the ignition module has been replaced already? You have or have not replaced the fuel injectors in it? Does the plug for that specific cylinder that continuously misfires look different? Have you done the "dollar bill" test at the exhaust to check for a bad valve/head gasket?

 

[Ttoyota]

I bought the bvh

Are there cylinders that seem to misfire more than the others? I get that all 8 are showing counts, but, lets say you graphed it... would there be 4 cylinders that tend to have more misfires than the rest? Can you post a screenshot of the cylinders with a bunch of misfire counts already? I'm curious as to which cylinders they are and where they are in the firing order and where they are on the engine.

I re-read your posts. So, the ignition module has been replaced already? You have or have not replaced the fuel injectors in it? Does the plug for that specific cylinder that continuously misfires look different? Have you done the "dollar bill" test at the exhaust to check for a bad valve/head gasket?

No sir on the dollar bill test. I'm offshore again so I cant jump on anything right away. Yes on the new fuel injectors. Bosch black knight 4 holes. yes i tried a new ignition module. I can say that the msfire count is all over the place. but I want to be able to give you correct information and in order for me to do that, I'll have to get back to you when i get off of here. I really appreciate all of your help.

 

[Christian Steffen]

So we've pretty well ruled out the ignition system right?

Did you say where you got the injectors from? Are they the stock size?