P0300 at idle
Thread Starter
Melting Slicks
Joined: Oct 2005
Posts: 2,877
Likes: 9
From: Ottawa Ontario
P0300 at idle
Hey guys
at idle my car will trigger P0300 sometimes. I hear no mis but it is what it is. My cam is pretty mild at 214 -226 559/569. I do not have rear 02's and they are cancelled out on the tune. It just started happening recently. I also recently had gas in my oil so I know I am getting a very rich condition. I just changed the oil now so its Okay. I have yet to see the code up while just driving around....just seems to be at start up. I have reseated my plug wires (msd) and pulled a plug. It had a black soot ring around the top of the plug but the rest of the plug looked okay. I have lowered my fuel pressure to 57 psi at idle as it was at 65psi and it seems to make no difference as the code returned but then I clear it and drive the car and I don't see it again till another start up. The car still needs to be tuned as it just has a base tune in it for now. This car has a fully built 403ci with a YSi trim on it.
Please let me know what you guys think
thanks
at idle my car will trigger P0300 sometimes. I hear no mis but it is what it is. My cam is pretty mild at 214 -226 559/569. I do not have rear 02's and they are cancelled out on the tune. It just started happening recently. I also recently had gas in my oil so I know I am getting a very rich condition. I just changed the oil now so its Okay. I have yet to see the code up while just driving around....just seems to be at start up. I have reseated my plug wires (msd) and pulled a plug. It had a black soot ring around the top of the plug but the rest of the plug looked okay. I have lowered my fuel pressure to 57 psi at idle as it was at 65psi and it seems to make no difference as the code returned but then I clear it and drive the car and I don't see it again till another start up. The car still needs to be tuned as it just has a base tune in it for now. This car has a fully built 403ci with a YSi trim on it.
Please let me know what you guys think
thanks
Last edited by MotleyDrew; Oct 21, 2007 at 12:25 PM.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Get the tune straightened out first. You can remove the idle misfire detection but it appears to be providing useful information right now by your description. Fuel in the oil is real bad by the way, you can lose bearings from this so I would get the turn squared away as soon as possible.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
Next time you see the flashing light at idle...give it a little gas, and hold the rpm's up a little above your idle point...say 1000-1200rpm, and just hold it there for 20-30 secs. If the CE light goes out, it's likely just a false misfire detection caused by the cam.
Even though yours is mild, it may have just enough lope to falsely set it off.
If the above test worked, when you get the car tuned, have your tuner set the minimum misfire detection rpm setting to a value slightly above your idle rpm, this will take care of it, and still keep misfire detection system working as normal, just not at idle.
For example, my car idles at 900rpm, I set the minimum detection rpm to 1200...and no more blinking CE light at idle!
Even though yours is mild, it may have just enough lope to falsely set it off.
If the above test worked, when you get the car tuned, have your tuner set the minimum misfire detection rpm setting to a value slightly above your idle rpm, this will take care of it, and still keep misfire detection system working as normal, just not at idle.
For example, my car idles at 900rpm, I set the minimum detection rpm to 1200...and no more blinking CE light at idle!
Thread Starter
Melting Slicks
Joined: Oct 2005
Posts: 2,877
Likes: 9
From: Ottawa Ontario
Next time you see the flashing light at idle...give it a little gas, and hold the rpm's up a little above your idle point...say 1000-1200rpm, and just hold it there for 20-30 secs. If the CE light goes out, it's likely just a false misfire detection caused by the cam.
Even though yours is mild, it may have just enough lope to falsely set it off.
If the above test worked, when you get the car tuned, have your tuner set the minimum misfire detection rpm setting to a value slightly above your idle rpm, this will take care of it, and still keep misfire detection system working as normal, just not at idle.
For example, my car idles at 900rpm, I set the minimum detection rpm to 1200...and no more blinking CE light at idle!
Even though yours is mild, it may have just enough lope to falsely set it off.
If the above test worked, when you get the car tuned, have your tuner set the minimum misfire detection rpm setting to a value slightly above your idle rpm, this will take care of it, and still keep misfire detection system working as normal, just not at idle.
For example, my car idles at 900rpm, I set the minimum detection rpm to 1200...and no more blinking CE light at idle!
My car idles at 850rpm
Under "Engine Diagnostics" I don't have the idle option in HP Tuners.
I have 3 options under revolution mode: Low RPM, Medium RPM, and High RPM.
This is what my values are at under Low RPM:
1000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000
1100 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000
1200 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000 32767.00000
