Z06 Steve

iTrader: (8)

I keep getting a random misfire CEL at idle. Can I adjust hptuners to tune this out or around it ???? Im a newbe so please be detailed thanks in advance!

LsoneGT

iTrader: (2)

Whats the code? If its a mechanical issue go ahead and fix it. If not post your tune up so we can see.

Caterpillar1

Castech 706 head cracks
Hey guys I have an 05 Chevy Silverado 1500 5.3 rebuilt the top end due to the infamous crack issue with these heads. I have a question . Before that here is what I have done . Hydraulic lifters with the full cage rods roller rockers pacesetter shorty headers all top end gaskets etc. I swapped the 706 out for 862 heads I have spark good compression fuel etc.. It is idling very rough like it's choking . Does the PCM need to be tuned due to the higher compression 862? Inside cylinders are firing or hot the out side are warm any help? New double platinum ac plugs too? I posted this in the PCM tuning thread but no response.
All parts replaced were factory spec. Only upgrade was the roller rockers even those are stock 1.7. An advice would be welcomed

Z06 Steve

iTrader: (8)

its PO300 no mechanical issue. Its a big cam and I need to desensitize some tables but don't what numbers go where. my file is too big to attach here how do I post it?

SladeX

I just disable the PO300 code. 3-No error code reported.

I'm tempted to turn it back on since I've smoothed out the idle on my engine a lot since the first cam I've installed... and I'm 4 cams later.

If you need to desensitize your knock sensors, its because you are getting knock retard on WOT runs and its not legitimate knock. If there is no knock retard detected at wot and part throttle, all you need is to shut off the code since most of us like lumpy idles and the ECU does not.

Z06 Steve

iTrader: (8)

yeah this occurs at idle start up I will give it a try thanks

Z06 Steve

iTrader: (8)

I shut off the code for po300 but the check eng light still flashes anyway around this?

SladeX

"Flashing" indicates misfire. Check DTC, make sure code is really off -"No error code reported". If flashing/misfire should trigger another code.

Z06 Steve

iTrader: (8)

After reaching operating temp the code isn't triggered anymore. How do I make the adj so the code is completely turned off and no flashing CEL?

Russ K

iTrader: (1)

Set the P0300 code back to stock. Then max out the idle misfire tables. Leave the higher rpm tables stock This way if you have a real misfire, the pcm will store the code for the missing cylinder.

Russ Kemp