GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |

5.3 P0300 after header install

Thread Tools
 
Search this Thread
 
Old Mar 23, 2014 | 09:27 PM
  #1  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default 5.3 P0300 after header install

2004 5.3 with black bear tune and 212/218 cam.


Just had to pull heads the get some broken bolts out so I could install my longtubes.

Got everything installed and started truck up. Everything ran okay. It stumbled at first drive but then went normal. Had a p0300 code come up and an expected o2 sensor code. Cleared those then drove 45miles to home. Let it sit for about 2 hours.

Went to start the motor and drive a mile to get food and bam, started stumbling and missing and the CEL was flashing. Cleared the codes, and then it happened immediately after again. Cleared that code and let it idle for a bit and all seemed well. Went to drive thru and the CEL started flashing so I revved it and then it went away. Has not been retuned yet. Ideas?
Reply
Old Mar 24, 2014 | 09:16 AM
  #2  
GMC93's Avatar
Launching!
 
Joined: Sep 2012
Posts: 236
Likes: 2
From: Lorena,Tx
Default

Check the wires... sounds like one might have come unseated
Reply
Old Mar 24, 2014 | 12:26 PM
  #3  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default

I will do that after work and see what I find.

Would it be a problem if I mounted the plug wire to the coil upside down where the wire meets the coil at the bend? I only flipped them to change the angle of the wire to keep it from burning on the headers.
Reply
Old Mar 24, 2014 | 12:27 PM
  #4  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default

Also getting a code that says bank 2 running too lean and bank 2 circuit 1 low voltage. Something along those lines, can't remember codes.
Reply
Old Mar 24, 2014 | 05:02 PM
  #5  
greasemykey's Avatar
TECH Fanatic
iTrader: (5)
 
Joined: Nov 2005
Posts: 1,152
Likes: 0
From: Portsmouth, VA
Default

sounds like a bad O2 sensor or bad connection
Reply
Old Mar 24, 2014 | 05:55 PM
  #6  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default

Went out after work and pushed in plug boots as far as possible. One seemed to click in one notch. Ran fine all the way home. Got a code saying bank 2 was too lean so I unplugged MAF, it idled like hell but the too lean code went away.
Reply
Old Mar 24, 2014 | 10:18 PM
  #7  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default

Okay pulled the codes that will NOT go away.

P0174 & P0151 - those two seem to pop up with each other every single time I drive and every now and then it throws out P0300 (random multiple cylinder misfire).

Should I start by replacing the passenger side upstream O2?
Reply
Old Mar 24, 2014 | 10:41 PM
  #8  
1FastBrick's Avatar
Custm2500's Rude Friend
15 Year Member
Loved
Liked
Community Favorite
iTrader: (17)
 
Joined: Apr 2007
Posts: 14,596
Likes: 900
From: JunkYard
Default

Did you get a tune after the header install?
Reply
Old Mar 25, 2014 | 06:41 AM
  #9  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default

No. Have not been retuned after the install. Just got er done two days ago.
Reply
Old Mar 25, 2014 | 02:16 PM
  #10  
skaffy03's Avatar
Thread Starter
On The Tree
 
Joined: May 2013
Posts: 161
Likes: 0
From: Ames, IA
Default

I'm pretty sure these o2 sensors are the factory ones and I have 165k miles now. Gonna swap it out and see what happens. I'll post up results
Reply



All times are GMT -5. The time now is 02:00 AM.