P0300, P0101, P0420 Please Help
12-15-2010, 05:23 PM
#1
P0300, P0101, P0420 Please Help Hopefully someone can help me figure out a problem I am having with my truck. I took it to the dealer last week for:
Tranny Cooler lines leaking
Steering Shaft Clunk
Cig. Lighter Inop
Blower Motor Inop
They had it for 5 days and I took it home Friday afternoon. After about 20 minutes, it started to Misfire at WOT @ 3500 RPM, CEL starts blinking. I limped it home, everything seemed fine while driving normally.
I couldn't make it back to the dealer until Monday, so I parked it.
Monday morning I took it back to the dealer and had a tech come for a ride with a scantool. Turns out I had a P0300(misfire) and a P0101 (MAF) stored. We went for a ride and found #1 cylinder was misfiring.
Obviously, the Misfire is the main issue. The only reason I brought it to the dealer is because I have the GMPP extended warranty. So I took it home and bought some plugs/wires so I wouldn't get stuck paying them for it when I could do it myself.
Today I did the Plugs/Wires and it still misfires at WOT but now @ 5000 RPM. It threw 3 codes P0300(misfire), P0101(MAF), P0420(catalyst Inefficiency).
So, I'm going to bring it back to the dealer tomorrow morning but wanted some opinions first.
Vehicle: 2005 GMC Sierra 2500HD 6.0L LQ4 w/ 87,000 Miles
Mods: K&N FIPK, SLP LMII Custom Catback. Both were installed when I purchased the truck in Dec. 2004 and have never had any issues until now.
The Tech tried telling me the CAI was causing the MAF issue, which I don't think is the problem.
Could the Misfire be caused by the MAF being bad?
I'm sure the coil pack is the problem, could this just be coincidence?
I know the P0420 is caused by raw fuel being dumped, so I'm not worried about that.
Any help would be greatly appreciated. I'm pissed and don;t really trust the dealer, I dropped off a Truck that ran perfectly fine and now it falls on it's face every time I get on it.
Thanks,
Tim
Tranny Cooler lines leaking
Steering Shaft Clunk
Cig. Lighter Inop
Blower Motor Inop
They had it for 5 days and I took it home Friday afternoon. After about 20 minutes, it started to Misfire at WOT @ 3500 RPM, CEL starts blinking. I limped it home, everything seemed fine while driving normally.
I couldn't make it back to the dealer until Monday, so I parked it.
Monday morning I took it back to the dealer and had a tech come for a ride with a scantool. Turns out I had a P0300(misfire) and a P0101 (MAF) stored. We went for a ride and found #1 cylinder was misfiring.
Obviously, the Misfire is the main issue. The only reason I brought it to the dealer is because I have the GMPP extended warranty. So I took it home and bought some plugs/wires so I wouldn't get stuck paying them for it when I could do it myself.
Today I did the Plugs/Wires and it still misfires at WOT but now @ 5000 RPM. It threw 3 codes P0300(misfire), P0101(MAF), P0420(catalyst Inefficiency).
So, I'm going to bring it back to the dealer tomorrow morning but wanted some opinions first.
Vehicle: 2005 GMC Sierra 2500HD 6.0L LQ4 w/ 87,000 Miles
Mods: K&N FIPK, SLP LMII Custom Catback. Both were installed when I purchased the truck in Dec. 2004 and have never had any issues until now.
The Tech tried telling me the CAI was causing the MAF issue, which I don't think is the problem.
Could the Misfire be caused by the MAF being bad?
I'm sure the coil pack is the problem, could this just be coincidence?
I know the P0420 is caused by raw fuel being dumped, so I'm not worried about that.
Any help would be greatly appreciated. I'm pissed and don;t really trust the dealer, I dropped off a Truck that ran perfectly fine and now it falls on it's face every time I get on it.
Thanks,
Tim
