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Backfire/Pops at idle

  • Thread starter Thread starter 281pony
  • Start date Start date Nov 25, 2004

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 25, 2004
#1
  • Nov 25, 2004
  • #1
i just got the car going again and fixed my noisy rockers. everything is good except for it backfires/pops at idle.

its about every 45 seconds. no codes. just have a simple question, before my plug wire was shot and it had an irractic around at throttle, its kind of doing that now at about 1200 rpm is all im letting it rev to.

my number 6 plug, you can see a small blue light by the boot, and the body is cracked. will cracked bodies cause them to misfire and cause the backfires? anything else i can check for? timing is at 10-12.
 

TrickStang37

New Member
Oct 17, 2004
292
0
0
Nov 25, 2004
#2
  • Nov 25, 2004
  • #2
yes, the fuel is not igniting in the combustion chamber. back fire in the exhaust is usually meaning too rich (lack of combustion).
 
C

crunchie12268

New Member
Aug 4, 2004
599
0
0
Manhattan, KS
Nov 25, 2004
#3
  • Nov 25, 2004
  • #3
yeah, you should get that fixed
 

TrickStang37

New Member
Oct 17, 2004
292
0
0
Nov 25, 2004
#4
  • Nov 25, 2004
  • #4
defintely change that plug wire. if its cracked, it probably sat on a header for a while. the wire is probably cooked, the resistance might be pretty high on that wire.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 25, 2004
#5
  • Nov 25, 2004
  • #5
sorry i didnt get back earlier, stangnet froze on me for a couple hours.

it is my PLUGS that are cracked, wires are perfect. i have taken out 4 plugs so far and 3 have been pretty severely cracked. i dont know how they all got cracked, they only have 14 miles on them.

it makes sense though. when you try to rev it a little, it has a weird hesitation/popping like my car did before when i wasn't firing on all 8 cylinders. it also smells rich, plugs smell like gas. so its got to be the cracked plugs causing misfiring, then the richness and backfiring as someone else mentioned.

it fires up perfect, idles perfect. just backfires once, sometimes twice about every 30-45 seconds. definately sounds like plugs doesn't it? too bad the damn stores are closed today.
 
J

jerry beach

Founding Member
May 20, 2002
2,671
0
46
Ocala,FL
Nov 25, 2004
#6
  • Nov 25, 2004
  • #6
"it is my PLUGS that are cracked, wires are perfect. i have taken out 4 plugs so far and 3 have been pretty severely cracked. i dont know how they all got cracked, they only have 14 miles on them. "

You gotta ask yourself how they got cracked. Were you playing baseball with them the day before? Over-tightening them could cause them to crack, I guess. They should not be very tight. I dont know how much experience you have working with stuff like this, I am just letting you know if you get stuff too tight it can cause you big problems. If you already know better, just disreguard this message.

 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
Nov 25, 2004
#7
  • Nov 25, 2004
  • #7
As a person trying to recover from chronic overtightning syndrome I am going to agree with Jerry did you overtighten them? You don't have to tighten them that much just snug them up. Are they the right plug for the car?
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 25, 2004
#8
  • Nov 25, 2004
  • #8
yep, 3924's in an edelbrock head.

i probably tightened them too much. no baseball, just a little tennis ill go easier on this set.
 
J

jerry beach

Founding Member
May 20, 2002
2,671
0
46
Ocala,FL
Nov 25, 2004
#9
  • Nov 25, 2004
  • #9
Man, you gotta chill. You did get that wrench out of there right? How bad was that after you took the motor out?
 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
Nov 25, 2004
#10
  • Nov 25, 2004
  • #10
Yeah since you got it running I assume you got your 1/2 inch wrench back. So tell us where was it lodged??
 
Reactions: Tbates

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 25, 2004
#11
  • Nov 25, 2004
  • #11
well, i took everything off. exhaust, upper intake, disconnected everything, ect to pull the motor. then when my cousin came over to help me remove my hood, he said i can get that.

he fiddled with the wrench for like an hour and then got it out. then i re-installed everything and got it running.

first thing my rockers were loud. turns out they were loose. so i pulled my drivers side valve cover and tightened them. then my passenger side was loud. pulled it and tightened them. my ****ty stock bolts stripped, i think 2 of them stripped. got pissed, tightened them all the best i could without stripping and now that problem is gone.

fired it up this morning to set timing and the backfiring is happening. once this is fixed i hope the car will make it to the triple digits in miles. just leaves me with figuring out what size of socket i need to remove my rocker bolts next time and hopefully everything is ok.

it was in the front sump, right at the bottom of the pan. just ended up fishing it around a bunch of crap in short.
 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
Nov 26, 2004
#12
  • Nov 26, 2004
  • #12
Glad you got it out man.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 26, 2004
#13
  • Nov 26, 2004
  • #13
thanks.

i made the mistake this morning of going to walmart at 6:45. i almost lost an arm just trying to escape with my spark plugs. people are crazy
 
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