General Maintenance & Repairs Leaks | Squeaks | Clunks | Rattles | Grinds

LS1 Misfire

Thread Tools
 
Search this Thread
 
Old 12-07-2011, 08:48 AM
  #1  
Teching In
Thread Starter
 
MYSLPSS's Avatar
 
Join Date: May 2009
Location: Budd Lake, NJ
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default LS1 Misfire

Hi, my car started to misfire randomly at idle. Eventually the SES light came on and it's a PO300 code (random misfire). Now it sounds like it's running on only seven cylinders. I checked and there was voltage from all eight coil packs. My next guess is a bad spark plug or possible fuel injector. I'm leaning toward a bad spark plug. Any suggestions on what else it could be?
Also, what is a good replacement spark plug for my car? I don't race it and it's stock.
Thanks, Mike
Old 12-08-2011, 08:16 AM
  #2  
Super Moderator
iTrader: (9)
 
Reckless's Avatar
 
Join Date: Nov 2001
Location: Canton, GA
Posts: 10,052
Received 32 Likes on 16 Posts

Default

Most commonly it ends up being a broken valve spring on cars that have aftermarket springs, but if you are sure your car is bone stock, then you are heading in the right direction.
Old 12-08-2011, 12:38 PM
  #3  
TECH Fanatic
 
ghardester's Avatar
 
Join Date: Aug 2006
Location: Knappa, Oregon
Posts: 1,386
Likes: 0
Received 54 Likes on 43 Posts

Default

Multiple Random Misfire. I would change the spark plugs and wires. If that isn't the problem at least you have eliminated a common source of random misfire and done some regular service.

If you are driving it as a street car, like I do, I would suggest putting in the AC Delco Iridium plugs it came with and some after market heavier plug wires, like Taylor or MDS.

Many people here use NKG plugs with great success. I don't recall which ones but someone should be along shortly to say.
Old 12-10-2011, 02:42 AM
  #4  
TECH Enthusiast
 
RikkiTorment's Avatar
 
Join Date: Mar 2009
Location: West Chester, PA
Posts: 522
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by ghardester
Multiple Random Misfire. I would change the spark plugs and wires. If that isn't the problem at least you have eliminated a common source of random misfire and done some regular service.

If you are driving it as a street car, like I do, I would suggest putting in the AC Delco Iridium plugs it came with and some after market heavier plug wires, like Taylor or MDS.

Many people here use NKG plugs with great success. I don't recall which ones but someone should be along shortly to say.
TR5's, TR55's, TR55-IX's, and TR6's




All times are GMT -5. The time now is 10:02 AM.