PCM Diagnostics & Tuning HP Tuners | Holley | Diablo
Sponsored by:
Sponsored by:

Help - Service Engine Soon Light came on!

Thread Tools
 
Search this Thread
 
Old 12-01-2006, 06:44 PM
  #1  
TECH Fanatic
Thread Starter
iTrader: (7)
 
nomorews6's Avatar
 
Join Date: Sep 2004
Location: TEXAS!!!
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default Help - Service Engine Soon Light came on!

I drove about 15 minutes, went to a store, came out 15 minutes later, drove down the road a few minutes got on it a tiny bit and then noticed 'service engine soon'. I took it to auto zone and it said "PO300" - the PCM has determined that multiple random misfires have occurred. Troublecode OBDII (Alpha) P Code. Is this something to be concerned about? What should I do?
Old 12-01-2006, 06:54 PM
  #2  
TECH Senior Member
 
2001NBMZ28's Avatar
 
Join Date: Dec 2001
Location: Jacksonville, FL
Posts: 5,399
Likes: 0
Received 3 Likes on 3 Posts

Default

P0300 can be hard to diagnose - I've thrown it a couple times over the years and just cleared it without any problems. You can look up the diagnostics for your year at gearchatter.com
Old 12-01-2006, 07:01 PM
  #3  
TECH Fanatic
Thread Starter
iTrader: (7)
 
nomorews6's Avatar
 
Join Date: Sep 2004
Location: TEXAS!!!
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default

should i stay away from driving it?
Old 12-01-2006, 07:14 PM
  #4  
TECH Senior Member
 
2001NBMZ28's Avatar
 
Join Date: Dec 2001
Location: Jacksonville, FL
Posts: 5,399
Likes: 0
Received 3 Likes on 3 Posts

Default

Did they clear the code for you and it came back on immediately the next ignition cycle? Fine to drive as long as it's not "flashing" on and off. If it was a fluke (plug just misfired or something) the SES for P0300 should turn itself off after 3 cycles without seeing a failure.
Old 12-01-2006, 08:22 PM
  #5  
TECH Fanatic
Thread Starter
iTrader: (7)
 
nomorews6's Avatar
 
Join Date: Sep 2004
Location: TEXAS!!!
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default

no they didn't clear it for me at all ... should they have?
Old 12-01-2006, 08:41 PM
  #6  
TECH Senior Member
 
2001NBMZ28's Avatar
 
Join Date: Dec 2001
Location: Jacksonville, FL
Posts: 5,399
Likes: 0
Received 3 Likes on 3 Posts

Default

Don't know what their policy is - maybe they just read them only, never got a code read at AutoZone? If it doesn't go off after 3 or 4 ignition cycles I'd do a manual PCM reset and see what happens.
Old 12-01-2006, 11:56 PM
  #7  
TECH Fanatic
Thread Starter
iTrader: (7)
 
nomorews6's Avatar
 
Join Date: Sep 2004
Location: TEXAS!!!
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default

how do you do a manual pcm reset and what will that do?
Old 12-02-2006, 11:51 AM
  #8  
TECH Fanatic
Thread Starter
iTrader: (7)
 
nomorews6's Avatar
 
Join Date: Sep 2004
Location: TEXAS!!!
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default

go figure - it just turned off by itself today! I hope this is a good thing
Old 12-02-2006, 12:09 PM
  #9  
TECH Resident
iTrader: (17)
 
ZL1Killa's Avatar
 
Join Date: Sep 2004
Location: NC - Charlotte area
Posts: 3,747
Likes: 0
Received 0 Likes on 0 Posts

Default

check your spark plugs check connections... as that is very easy to do and could be a problem. I have had a wire just not snap on all the way to where i had misfires (but i was logging w/efilive and i was like wtf)... so i checked all wires and booya




All times are GMT -5. The time now is 12:59 PM.