P0300 Code (Misfire at low RPM range) Need LS1Tech Diagnostics.
11-12-2003, 12:39 PM
#1
TECH Regular
Thread Starter
Join Date: Apr 2003
Location: Atlanta, GA
Posts: 413
Likes: 0
Received 0 Likes
on
0 Posts
P0300 Code (Misfire at low RPM range) Need LS1Tech Diagnostics. I appreciate it if anyone has any extended information that I could look into about this problem. The scenario, I
am leaving Taco Bell coming home about 2 miles from home. I am at a redlight just starting to go through the gears
and it sound and feels like it lost 2-3 cylinders. I then press the gas about 30-40% and it clears up but when I
give it gas at low RPM and low Throttle Position it is misfiring pretty badly. It will easily go away when you
press the accellerator harder and it will run smooth as glass but it is like the coil packs quit firing. I hooked
AutoTap up and read the P0300 Codes. I then set it to log Misfires on all 8 cylinders and noticed it would go from
1,3,5,7 in a certain order that I cannot remember now but it was that set of cylinders the misfire was detected. I
started this diagnostics @ 1:30 A.M. this morning as I was @ Taco Bell at around 1:00 A.M. picking something up to
eat. I am going tonight and do some more diagnostics on reading some of the Sensor settings when it is misfiring.
I thought it might be a plug wire as it clears up when you mash on the gas but AutoTap is saying that like a whole
side or something 1,3,5,7 is misfiring when the happens. I have done preliminary searches and have read things
like this error could be related to Vacuum pressure, Fuel Pressure, (Fuel Pressure Regulator), Injectors, etc.
Nothing seems to be a definite clue in. All that is done mechanically to the car is long tube headers and a Lid
with stock FRAM filter. This all happened months after all this work is done. I was just going to read the sensors
tonight and see where they are showing to see if I can visually see what is going on but if anyone might have any
ideas I would be greatly appreciative as I assume I will have to take it to the Dealer tommorow if I can't figure
it out tonight, as I don't have alot of diagnostic tools other than Autotap and basic hand tools. I did have to
loosten the coil packs on the passenger side when I installed the headers but I don't know what (cylinder numbers)
each side is so I don't know if I might have pinched a wire and it is causing problems now. I figure checking the
TPS sensor for correct reading could be something as it goes away when it goes past a certain point, But that
doesn't explain why only certain cylinders are misfiring.
am leaving Taco Bell coming home about 2 miles from home. I am at a redlight just starting to go through the gears
and it sound and feels like it lost 2-3 cylinders. I then press the gas about 30-40% and it clears up but when I
give it gas at low RPM and low Throttle Position it is misfiring pretty badly. It will easily go away when you
press the accellerator harder and it will run smooth as glass but it is like the coil packs quit firing. I hooked
AutoTap up and read the P0300 Codes. I then set it to log Misfires on all 8 cylinders and noticed it would go from
1,3,5,7 in a certain order that I cannot remember now but it was that set of cylinders the misfire was detected. I
started this diagnostics @ 1:30 A.M. this morning as I was @ Taco Bell at around 1:00 A.M. picking something up to
eat. I am going tonight and do some more diagnostics on reading some of the Sensor settings when it is misfiring.
I thought it might be a plug wire as it clears up when you mash on the gas but AutoTap is saying that like a whole
side or something 1,3,5,7 is misfiring when the happens. I have done preliminary searches and have read things
like this error could be related to Vacuum pressure, Fuel Pressure, (Fuel Pressure Regulator), Injectors, etc.
Nothing seems to be a definite clue in. All that is done mechanically to the car is long tube headers and a Lid
with stock FRAM filter. This all happened months after all this work is done. I was just going to read the sensors
tonight and see where they are showing to see if I can visually see what is going on but if anyone might have any
ideas I would be greatly appreciative as I assume I will have to take it to the Dealer tommorow if I can't figure
it out tonight, as I don't have alot of diagnostic tools other than Autotap and basic hand tools. I did have to
loosten the coil packs on the passenger side when I installed the headers but I don't know what (cylinder numbers)
each side is so I don't know if I might have pinched a wire and it is causing problems now. I figure checking the
TPS sensor for correct reading could be something as it goes away when it goes past a certain point, But that
doesn't explain why only certain cylinders are misfiring.
