I have the same problem with my car. It only seems to throw the code at idle. I noticed it after installing my cams. I also am hoping to find a solution to this problem. After it throws the code the idle seems to go to sh**. It starts to get rough. Are you experencing this also?

 

A br8es plug is just like a bpr8es except that it doesnt have a projected tip. People use those plugs when really hig boost or nitrous is used. I still dont think that the plugs are your problem

 

the 0300 codes come on randomly...sometimes while i'm driving.....sometimes immediately after cold start....sometimes at the light.

 

Curious, I started to get the p0300 code after the custom flash, but the cam where replace in that occasion also, so I don't know if it is due to the cams or the custom flash..

 

2003 has a TSB for a reflash to solve the problem, just had it done on mine. I was getting random P0300 codes and now no more!! Not sure what year your car is but, Good Luck

 

My car is a 2003 also.. where did you solve the problem..? at the dealer..?

The thing is that if they fix this I will loose the custom flash, and I will have to send the ECU for another re-flash, my only issue is the time I will spend without my car.

Thanks,

Miguel

 

There are a few threads on this problem. What I'm hearing is:

1) There is more than one "update" to the firmware and not all dealerships have the latest.
2) There may be dealerships that will flash the ECU off-the-car for a nominal fee

In the meantime I'm strongly considering the CReader OBDII device for sale on eBay recommended in threads by a member here...

 

This is what I did to fix the same problem on my car. I have been over 15,000 miles without the P0300 popping up since I did that.

 

I believe my car was having this problem before I was tuned... but can't exactly remember when it started. It's started to misfire very rarely at high rpms now... but oftenly at idle still. I want to try any other fixes besides getting the dealer reflash then paying s/h to have my ecu reflashed back to it's previous map on top of the dealer flash.

What are the disadvantages or side-effects from gapping plugs too tight? I know if plugs aren't gapped tight enough, it could cause misfires... is this also true if plugs are gapped too tight? Does anyone have a knowledgable opinion on what heat range I should be using on my setup w/ the methanol? and a suggest gap? Any other suggestions on how to fix this problem?

 

Don't waste your time by changing anything that is working properly, and don't get the dealer reflash. You'll spend time and money, and you probably won't fix the glitch.

Go to Ebay and get a "CReader" OBDII scanner. Plug it in to the OBDII port and tuck it under the dash. Leave it plugged in, and you'll never get the PO300 misfire again.

 

I started getting that code to. I had my ecu reflashed at the dealership and have not had a problem for the last 3000 miles. Oh and I have cams too.

--Josh

 

Will this Creader erase other codes too or just the P0300?

 

it will erase all codes

 

Then it may do more harm than good since you're loosing the bad condition notification feature of the ECU. So there's trade-off.

 

I run a C-Reader myself and watch the display when I get a light just to make sure it reads P0300 before it clears ... I use a strip of velcro which uses the nearby screw on the bottom section of the dash so it sits right there staring up at me all the time so I can read it.