I upgraded to the SMART and was re-runed at the Turbo Trix tuning day in NJ.

I had the 0300 code early in my ownership of my 2003 Evo VIII. That seemed to be resolved. Unfortunately, it is back after my upgrade to SMART and re-tune.

I can actually feel the car stumble, look down and see the code. Any suggestions would be helpful.

Thanks.

SF

 

Is your C-reader plugged in?

-shiv

 

Check all of your boost piping to ensure that all couplings are installed properly secure. They have a tendance to slip and cause boost leaks that throw the code. --Expecially down by the IC.-- Also, head to an autoparts store and buy a can of MAF Sensor cleaner. If you run a cone (K&N) style filter the oil on the filter CAN coat the MAF enough to cause codes to be thrown. We have seen this twice here at our shop in Northern Utah!!

If you are running Magnacore wires you will also get the issue.

 

Shiv,

The c-reader is plugged in and clears the codes. However, shouldn't I be concerned that I am getting the codes in the first place?

Thanks.

SF

 

SMART will make you throw a PO300, because it has timing advance set on purpose to improve drivability. The ECU sees this and does not think it should be there, which causes it to throw a PO300. Its not dangerous, just outside of a parameter that the ECU looks for. However, if your Creader is working properly, you should not feel the stumble, as it intercepts them and takes that part away. If it is still physically stumbling when the creader is plugged in, it is likely that you have a defective creader.

If you don't want to use the creader, you can get rid of the PO300 in a more permanant way by changing only the positive values (0.1 - whatever) to zero. Leave the negative values alone, as they're there for protection. Of course you'll lose the extra drivability as the car comes up into boost that SMART offers, but it'll solve that PO300 problem.


Hope this helps.

 

Noize,

Thanks, I think that will be helpful. I have a mini-battery and had not run the car for a while. The battery had a little difficulty turning over the car, so I unplugged the c-reader (It does draw a ittle power from the battery). I did not understand that it is performing a function other than clearing codes.

I will leave it in while driving and see if this clears up my problem. If I don't feel the stumble but still throw codes, should I be concerned?

Thanks.

SF

 

Not at all. It will still throw the codes because of the advance. If you still feel the stumble with the creader plugged in, let me know.

 

Hey Noize,

I have felt this stumble with the creader plugged in before (custom tuned smart 0+). The creader always clears the code a few seconds later, but I do still feel the stumble and the car runs poorly for a few seconds until it resets itself with the creader. Sorry to hijack the thread, but it seems like I have experienced the same thing.

Thanks,
Adam

 

my car was never prone to 0300 until recently. i've found that with a frequent plug change the 0300 is less frequent. say i change them ever 2 oil changes or so. always gap to .024 or so.

 

if you feel the hesitation, you are actually getting misfire. its not just throwing a code because it feels like it.

i would start backing out some of the positive timing in the smart maps. maybe reduce it by 50%, then test it for awhile and see how it goes.

I have completely removed it in mine, just because i would rather not have any drivability and misfiring issues.