racer135

iTrader: (2)

When running big cams advancing the timing helps them have a smother idle. Why running too much timing advance at idle with big cams cause a P0300 misfire code? How much is too much timing at idle?

racer135

iTrader: (2)

No one? Would it be possible that advance in the teens would complete the combustion while still on the compression stroke? i.e Just before TDC? On my car if I use 8* I am OK but a 9* and a 10* at idle throws a P0300.

I believe the P0300 is throw when the ECU is looking to get stoich at idle and it oscillates between rich and lean. Wheh the idle gets really rough my wideband shows a very lean condition. And after that I usually get the code. Maybe running open loop at idle helps.

Raceghost

iTrader: (4)

I threw that code a bunch when I dropped my Kelfords in. It looks like we are virtually running the same upgrades, what map version are you on?

racer135

iTrader: (2)

Map version? Do you mean ROM ID? I run stock one 9642008 modified for ECU Boost, WGDC upward correction, Boost Log, Pherphery bits and a few other things (and obviously the timing and fuel maps) but it is still the same ID that came with the car. I can disable P0300 and I will not get the code (it is disable righ now) I am just trying to find the rationale for the code. No reason to disabel it if I can tune it out and still leave it enable in the event of a real misfire.

Raceghost

iTrader: (4)

That is exactly what I mean, and yes, I was on that rom stock as well. I then upgraded to the 96420011 rom, and then finally got the 94170015 rom to work. I am utilizing the 0015 rom as we speak. In all of them, I threw the p0300 code no matter what, had to disable it.

I do agree with you that leaving it disabled is playing russion rulet on which on is real knock, and which ones are not. Iwould like to reenable mine, but have not been able to find what the heck happens.

I did log at crank and start up, and you would be supprosed the amount of knock kelfords get you when you first crank the car. Try it, start your log why you have accessorie on, and then start the car. Look for the knock in the startup area. I was seeing 100 + accounts at engine crank. I then posted a thread on startup code and what is happening to cause that much knock at crank. This amount of knock will fill up your container or memory that throws the code on certain amount of knock sum. Walla, your p0300 code CEL light is on. Also, I would have a stable car, drive 45 miles, see the CEL light flash twice, but when I pulled in lets say for a drink, let the car idle for ten minutes, and CEL light on again... Atleast that is where I tracked mine to. SO I really think the p0300 code is not the fact that your knocking, it is triggered when a certain amount of knock is reached... As to tuning that out, and weather or not you play with upping that amount is questionable. Your not achieving your results if you up the amount of times it takes to triger that sort of p300 code.

One mor edit for good measure: I have a map that has 1-2 counts of knock rarely throughout the range, I will run this and see if my theory on the p0300 code is true, and if my listed conclusions are acurate. I will reenable the p0300 code and see when it throws again, and if it does. If the p0300 code does, then I know that it has to do with knock sum, and not that the car is misfifing so badly that it sets it off.

I am no expert and am only reemphasizing what it is I have seen. Hope that helps.

racer135

iTrader: (2)

Raceghost,

The P0300 code is a misfire code. You can get a misfire by having too much advance without the required fuel enrichment. That happens when running open loop at idle and advancing timing to quiet down cams. Spark plugs can also throw a code.

A misfire may be seen by the knock sensor as knock but I believe it has nothing to do with knock. You will know when you misfire at idle because the car will shake and your wideband will go lean. How much timing you were running with the Kelford at idle?

Raceghost

iTrader: (4)

I started with 8, and am in the 11's in the 20-40 area...
It didnt like 8's all the way to 60 load there in idle, I was having issues with it fluttering and wanting to die. I have the "Idle sensitivity" in the timing area of the rom set to 148, 8, 8.

Any thought's? I am hoping that we can figure this thing out...lol.

lan_evo_mr9

iTrader: (10)

Easy, disable the p0300 code in periphery bits.

Slo_crx1

iTrader: (9)

Try reducing the timing adders that are present in the "boost enhancement adv/ret map 2" if you want to try and keep the p0300 off the radar without disabling it. Reducing that table by a few degrees has actually kept my p0300 off for about 2.5 years now, only noticeable difference is engine decel (engine braking) seems to be much more noticeable with less timing in the map, other than that it has worked great for me for years. Other things in the mix will also set that code, such as a slight fluctuation in the crank and cam signals as well. Honestly, just disable it and leave it off.