Plug gap closed?
11-19-2006, 06:43 PM
#1
12 Second Club
Thread Starter
iTrader: (4)
Join Date: Sep 2005
Location: Fort Myers, FL
Posts: 589
Likes: 0
Received 0 Likes
on
0 Posts
Plug gap closed? Backstory contained within: https://ls1tech.com/forums/general-maintenance-repairs/608175-stumbles-stalls.html
New info:
I went WOT from about 20-90mph and when I let off my car had a bad stumble like it wanted to die, and was misfiring and backfiring. Since this was a previous symptom I went through the usual routine and waited for the issue to go away.
It didn't... I drove home and the ses light was showing misfires.
I scanned the car and found the code P0307, cyl 7 misfire. I pull the plug and notice that the gap is closed..
I replace the plug, fire it up, no more misfires, everything seems to be ok.
Why/how would a plugs gap get closed?
New info:
I went WOT from about 20-90mph and when I let off my car had a bad stumble like it wanted to die, and was misfiring and backfiring. Since this was a previous symptom I went through the usual routine and waited for the issue to go away.
It didn't... I drove home and the ses light was showing misfires.
I scanned the car and found the code P0307, cyl 7 misfire. I pull the plug and notice that the gap is closed..
I replace the plug, fire it up, no more misfires, everything seems to be ok.
Why/how would a plugs gap get closed?
Trending Topics
11-19-2006, 08:18 PM
#8
Originally Posted by autotrix
Under the hard accel you probably knocked a big piece of carbon loose. It smacked the plug before exiting on exhaust.
11-19-2006, 08:33 PM
#9
12 Second Club
Thread Starter
iTrader: (4)
Join Date: Sep 2005
Location: Fort Myers, FL
Posts: 589
Likes: 0
Received 0 Likes
on
0 Posts
There doesn't appear to be any other damage.. I've taken the car about 2 miles since changing the plug, car idles fine, drives fine, pulls fine.. no smoke, everything *appears* normal.
I'm hoping that's all it was, with all the problems people have with Cyl #7, I'm quite antsy.
I'm hoping that's all it was, with all the problems people have with Cyl #7, I'm quite antsy.
11-19-2006, 09:04 PM
#10
Launching!
iTrader: (7)
Join Date: Apr 2006
Location: Leon, IA
Posts: 254
Likes: 0
Received 0 Likes
on
0 Posts
Have you ever seafoam'ed your car?? If not, and you have quite a few miles i'd also say some carbon. I had a similar thing happen to a cavalier of mine. Gap was like .015, but before that there was alot of white smoke out the back though.
11-20-2006, 04:41 AM
#11
Just to be safe, I'd remove the oil fill cap while the car idles. If air is blowing out of the filler neck, there's bigger problems. May also want to do a pressure or leak down test on number 7 to make sure that it wasn't a chunk of the piston or valve. It's possible to lose a chunk without throwing codes.
11-20-2006, 03:41 PM
#14
12 Second Club
Thread Starter
iTrader: (4)
Join Date: Sep 2005
Location: Fort Myers, FL
Posts: 589
Likes: 0
Received 0 Likes
on
0 Posts
My car needs tuned pretty bad, it's got full exhaust/full intake and has never been tuned.. I was having some problems with stalling after adding the intake that people said were likely tune related.
I run 93 octane gas, the plug was black as the small images show.
There's a noticeable ticking sound now, it's really only heard at idle, as the rpms climb the sound speeds up and then cannot be heard. I'm not sure if the many backfires may have created an exhaust leak, or maybe a pushrod is bent or what. Car drives fine though thus far.
I run 93 octane gas, the plug was black as the small images show.
There's a noticeable ticking sound now, it's really only heard at idle, as the rpms climb the sound speeds up and then cannot be heard. I'm not sure if the many backfires may have created an exhaust leak, or maybe a pushrod is bent or what. Car drives fine though thus far.
11-20-2006, 04:08 PM
#15
Closed ex-Sponsor Account
iTrader: (5)
Join Date: Nov 2006
Location: Tulsa, OK
Posts: 461
Likes: 0
Received 0 Likes
on
0 Posts
Yeah the push rods on these motors have been known to fail...oh well, a small price to pay for such a powermill!
More of a problem on first gen ls1's.
More of a problem on first gen ls1's.
11-20-2006, 04:26 PM
#16
12 Second Club
Thread Starter
iTrader: (4)
Join Date: Sep 2005
Location: Fort Myers, FL
Posts: 589
Likes: 0
Received 0 Likes
on
0 Posts
How well would the car drive if the pushrod was actually bent?
I mostly hear of the Pushrods failing due to overrevving, which was not the case with this Auto LS1.
I mostly hear of the Pushrods failing due to overrevving, which was not the case with this Auto LS1.
11-20-2006, 05:36 PM
#17
12 Second Club
Thread Starter
iTrader: (4)
Join Date: Sep 2005
Location: Fort Myers, FL
Posts: 589
Likes: 0
Received 0 Likes
on
0 Posts
The tapping sound is most evident around 1k rpms. Anything above that and you can't hear it anymore.. On my way home today I figured I'd see how the car liked some peddle.
I brake torqued it up a bit, let loose on the break and hammered the gas, The Nittos broke loose car spun up through first, shifted into second, kept spinning and I let off.
There was a trail of 555R smoke and the car seemed fine.
The noise continues. Hmm....
I brake torqued it up a bit, let loose on the break and hammered the gas, The Nittos broke loose car spun up through first, shifted into second, kept spinning and I let off.
There was a trail of 555R smoke and the car seemed fine.
The noise continues. Hmm....
11-20-2006, 09:30 PM
#18
Closed ex-Sponsor Account
iTrader: (5)
Join Date: Nov 2006
Location: Tulsa, OK
Posts: 461
Likes: 0
Received 0 Likes
on
0 Posts
Yeah it is crazy, but the car had one broken and two bent on the same bank. I checked the other side for grins and found that 5 were bent. Bad enough to where they have elongated their passthur holes in the head. (not supposed to even touch there) If you were to hold one of the 7 pushrods up to me and ask if the car was running I would reply no!!