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First time installing Spark plugs.Need help

  • Thread starter Thread starter Greenfive-oh8
  • Start date Start date Jun 5, 2005
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Greenfive-oh8

New Member
Oct 10, 2004
30
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Fort Lauderdale, FL
Jun 5, 2005
#1
  • Jun 5, 2005
  • #1
I changed out my spark plugs because i thought it needed new ones, i labeled every stock sparkplug wire that i took off so i knew where to put it back on, i took off the old ones, and put in the new ones, except for two, because i ran out of time and none of the plugs didn't really need changing anyway (they were bosh platinums) and i put in 6 bosch #25's , while i was doing that i deceided i wanted to take off my intake plaque and paint it so i took it off, now when i started up my car the idle was really funky it kept going from like 800 rpm's to like 400 , i knew something was wrong, so i put just the the little bolts back into the intake plaque thinking it was sucking air threw there, the idle became normal again at like 7oo rpms, so i drove my car down the street and i noticed everytime i put the car under acceleration it would spudder and eventually pick up speed while still spudddering untill, i let off the gas or kept it at that speed it would stop. it was like i had the car in higher gear than what is normal. what's going on?

i definately picked the wrong car to do my first tune up on
 
3

331 stang91

Member
Oct 16, 2004
261
0
16
wisconsin
Jun 5, 2005
#2
  • Jun 5, 2005
  • #2
When you put your plague back on did you maybe damage the gasket or put the gasket on wrong?
 

sunil6784

Member
Mar 31, 2005
620
0
18
Boston, MA
Jun 5, 2005
#3
  • Jun 5, 2005
  • #3
Sounds like the firing order is frigged up...

Did you do all the wires at once ? or one at a time?

Did you take the wires off the distributor cap ?
 

stang22

Active Member
Jan 29, 2003
1,318
7
38
Washington, D.C.
Jun 5, 2005
#4
  • Jun 5, 2005
  • #4
If you are looking at the distributor cap, you will see a number 1 on it. That is the number one plug wire. In a counter-clockwise motion, your firing order is 13726548. If you are looking at the front of your engine, the first plug of the left side head is plug #1, then straight back, 2,3,4. The first plug on your right side head is plug #5, then 6,7,8. Double check all of your vacuum lines and make sure your plugs are gapped to the correct gap.

Takin the intake plate off to polish/paint it will not affect a single thing. Unless you pulled the entire upper intake off to paint it and botched something up when putting it back on.

Tim
 
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331 stang91

Member
Oct 16, 2004
261
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16
wisconsin
Jun 5, 2005
#5
  • Jun 5, 2005
  • #5
thats what I thought he did took off the upper intake and maybe messed up the gasket or something along those lines.
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Jun 5, 2005
#6
  • Jun 5, 2005
  • #6
I agree with checking the firing order...probably just two mixed up and an easy fix.

BTW -- congrats on your first tune-up.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Jun 5, 2005
#7
  • Jun 5, 2005
  • #7
so you only swapped 6 of the 8 plugs? did you gap the new spark plugs?
 
E

emagdnim

Active Member
Feb 5, 2003
391
15
28
Jun 6, 2005
#8
  • Jun 6, 2005
  • #8
88SC_GT said:
so you only swapped 6 of the 8 plugs? did you gap the new spark plugs?
Click to expand...

Its definatly a fireing order issue.. trace each wire i had this exact problem .
 
E

Eric @ DMS

New Member
Jun 4, 2005
8
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Jun 6, 2005
#9
  • Jun 6, 2005
  • #9
This sounds like a common problem experienced. My initial thought was the firing order as well.
 
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BaXTeR3221

Member
Jan 12, 2004
917
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16
Orange County, NY
Jun 6, 2005
#10
  • Jun 6, 2005
  • #10
did the same thing last week, had the same results. Ended up having the 6 and 7 wires on the wrong plugs.
 

Greenfive-oh8

New Member
Oct 10, 2004
30
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0
Fort Lauderdale, FL
Jun 6, 2005
#11
  • Jun 6, 2005
  • #11
Thanks for the help, i'm going to go check to see if i put the wrong wire on the wrong plug, while my engine's cold,

oh and to answer your questions
no i did not take off the upper intake just the little plaque on top of it

i did the whole driver side at one time then i did only two on the pass. side

i did not touch the distributor

and i did not gap the new plugs except for one and all the rest looked ok

well ima go get dirty, wish me luck
 

darthcual

Member
Mar 31, 2005
985
19
18
Arlington, TX
Jun 6, 2005
#12
  • Jun 6, 2005
  • #12
heres a little tip maybe someone has mentioned b4 but i'll say again change the spark plugs one at a time. Never pull them all off. just unplug one, change the plug, plug it back in. that way there is never a question about firing order. Hope that helps.

*edit i see that u stated in a later post that u did do one at a time but it looked like from the first post u took'em all off sorry for the confusion.

DC
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Jun 6, 2005
#13
  • Jun 6, 2005
  • #13
Greenfive-oh8 said:
and i did not gap the new plugs except for one and all the rest looked ok
Click to expand...

that is why i asked about the gap. its kind of hard to eye thousands of an inch with your eye isint it? having them gapped wrong wont help things either.
 

cobradvm

New Member
Sep 2, 2003
245
1
0
Woodinville, WA
Jun 6, 2005
#14
  • Jun 6, 2005
  • #14
Yup need to get them gapped - usually at 0.050 of an inch. Also check and make sure none of them cracked - had that happen and the car would stumble under load. Make sure all your connections are okay, and as said above, when changing plugs only do one at a time to make sure the firing order doesn't get messed up.
 
P

Project89

New Member
Apr 24, 2005
94
0
0
Panama City, Florida
Jun 6, 2005
#15
  • Jun 6, 2005
  • #15
Since you are going to be troubleshooting you should go ahead and replace the two plugs you had originally not replaced.
 
8

89lxsport50

10 Year Member
Feb 25, 2003
550
5
39
Franklin Tennessee
Jun 6, 2005
#16
  • Jun 6, 2005
  • #16
Definitely gap your plugs. It is also very easy to damage a spark plug wire by pulling and tugging on it, especially if it is on tight. To get to those 2 plugs on the passenger side remove the air intake hose and undo the smaller emmissions hose that runs above the plugs. The plug nearest the firewall is the hardest to get. Take your time and be careful.
 
8

89 Saleen#455

Founding Member
Dec 29, 1999
519
5
39
New England
Jun 6, 2005
#17
  • Jun 6, 2005
  • #17
Also check the routing of your new spark plug wires. You may have burnt one of your new wires on the exhaust header and its arching out against something metal?
 

Car RamRod

Banned
Mar 30, 2005
623
0
0
Queens, NYC
Jun 6, 2005
#18
  • Jun 6, 2005
  • #18
darthcual said:
heres a little tip maybe someone has mentioned b4 but i'll say again change the spark plugs one at a time. Never pull them all off. just unplug one, change the plug, plug it back in. that way there is never a question about firing order. Hope that helps.
DC
Click to expand...
this is good advice, this method is especially important when changing the wires too.
 

Greenfive-oh8

New Member
Oct 10, 2004
30
0
0
Fort Lauderdale, FL
Jun 7, 2005
#19
  • Jun 7, 2005
  • #19
my spark plug wires all lead to the right plug, i just triple checked, could not gapping the spark plugs really cause all these problems?
where are the vaccum lines that i should check?



thanks alot , not only are your guys' advice helping me, its giving me some enthusiasm and stopping me from putting a couple fist size dents in my fender
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Jun 7, 2005
#20
  • Jun 7, 2005
  • #20
someone just mentioned what i was thinking besides gapping them. did your plug wire get burnt? inspect all the wires, if its arcing on the headers or anything that will cause the symptoms your having.

i re-read your original post and my car did the EXACT same thing from a burnt plug wire. you can get a spark plug gapper for 99 cents and they should be gapped between .052-0.056. i always go for the middle.

good luck.
 
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