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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

rough idle..

  • Thread starter Thread starter madonionrs
  • Start date Start date Apr 18, 2004
M

madonionrs

New Member
Jun 7, 2003
250
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0
Buffalo NY
Apr 18, 2004
#1
  • Apr 18, 2004
  • #1
I changed out my plugs yesterday (I started a thread to show your guys... they were bad)

Yesterday and today it stalled when I started it and had a rough idle for a few minutes.

Would this have anything to do with the plugs/wires?
Or, is it just my IAB Valve going bad again?
 
M

madonionrs

New Member
Jun 7, 2003
250
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0
Buffalo NY
Apr 18, 2004
#2
  • Apr 18, 2004
  • #2
I assume not?
 
S

SVT95

New Member
Apr 12, 2004
8
0
0
chicago area
Apr 18, 2004
#3
  • Apr 18, 2004
  • #3
check the gap to see if its right. make sure you used dielectric grease on the tips of plugs.
 
R

redterror302

Founding Member
Jun 29, 2002
895
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0
Mertztown, PA or State College, PA
Apr 18, 2004
#4
  • Apr 18, 2004
  • #4
What did you change when you did this? Just the plugs, or plugs and wires?

Sounds like you have a possible wire mixed up, so it is missing. Did you gap the spark plugs correctly?
 
M

madonionrs

New Member
Jun 7, 2003
250
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Buffalo NY
Apr 18, 2004
#5
  • Apr 18, 2004
  • #5
5.0GT said:
What did you change when you did this? Just the plugs, or plugs and wires?

Sounds like you have a possible wire mixed up, so it is missing. Did you gap the spark plugs correctly?
Click to expand...

I gapped them at .40

I did NOT use any grease, was I supposed to? They all went in pretty easy, the second to the last on the left hand side was pretty hard though.

Same wires, and I did not mix them up.. did one at a time. (unless they were already mixed up
 
M

madonionrs

New Member
Jun 7, 2003
250
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0
Buffalo NY
Apr 18, 2004
#6
  • Apr 18, 2004
  • #6
ttt
 
5

5.0guy

Member
Apr 17, 2004
320
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17
MI
Apr 18, 2004
#7
  • Apr 18, 2004
  • #7
throw some dielectric grease on the tips where the boot connects. and next time, put a little anti-seize on the threaded portion that goes into the head. u could also clean out the IAB and check ur MAF, my stuff was kinda dirty and that took care of my rough idle. alos check the voltage on ur tps..should be as close to 1 as possible, not over
 
M

madonionrs

New Member
Jun 7, 2003
250
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0
Buffalo NY
Apr 18, 2004
#8
  • Apr 18, 2004
  • #8
5.0guy said:
throw some dielectric grease on the tips where the boot connects. and next time, put a little anti-seize on the threaded portion that goes into the head. u could also clean out the IAB and check ur MAF, my stuff was kinda dirty and that took care of my rough idle. alos check the voltage on ur tps..should be as close to 1 as possible, not over
Click to expand...

Thanks!
I'm going to get some Dielectric grease for the plugs.

Btw, what type of sprays should I use to clean the IAB/MAF?

Also, how do you check your tps?

Thanks for all your support guys/girls!
 
5

5.0guy

Member
Apr 17, 2004
320
0
17
MI
Apr 19, 2004
#9
  • Apr 19, 2004
  • #9
if ur MAF still has the screen, check to see if it's dirty, if it is, clean it. http://www.budgetperformance.com/articles/iab/ that should answer ur questions

also, get ur computer scanned to see if it's throwin any codes...u may need new o2 sensors
 
8

89lxsport50

10 Year Member
Feb 25, 2003
550
5
39
Franklin Tennessee
Apr 19, 2004
#10
  • Apr 19, 2004
  • #10
Isn't the stock gap .054?
 
R

redterror302

Founding Member
Jun 29, 2002
895
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0
Mertztown, PA or State College, PA
Apr 19, 2004
#11
  • Apr 19, 2004
  • #11
89lxsport50 said:
Isn't the stock gap .054?
Click to expand...

yup
 
5

5.0guy

Member
Apr 17, 2004
320
0
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MI
Apr 19, 2004
#12
  • Apr 19, 2004
  • #12
damn, my gap is not that big. I should prolly re-gap them, huh?
 
8

89lxsport50

10 Year Member
Feb 25, 2003
550
5
39
Franklin Tennessee
Apr 19, 2004
#13
  • Apr 19, 2004
  • #13
I would.
 
M

madonionrs

New Member
Jun 7, 2003
250
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0
Buffalo NY
Apr 19, 2004
#14
  • Apr 19, 2004
  • #14
5.0guy said:
damn, my gap is not that big. I should prolly re-gap them, huh?
Click to expand...

Yeah.... after I put in new plugs with a gap of .4 my car stalls everytime I start it.

I'm putting it up to .56 atm.
 

StangFireman

Founding Member
Jan 5, 2001
2,113
0
0
Lebanon, Pennsylvania
Apr 19, 2004
#15
  • Apr 19, 2004
  • #15
If you have a good ignition, .040 shouldn't hurt you. As I was once told by a good friend of mine that's crew chief for a SSO car, "I've never seen more hp by gapping bigger, but I've seen more by gapping smaller".
I run .040 in my Factory Stock car. Of course it's not a daily driver either.
 
S

sleeper89

New Member
Nov 18, 2002
388
0
0
Toronto, Ontario
Apr 19, 2004
#16
  • Apr 19, 2004
  • #16
madonionrs - i'd be inclined to check your wires/rotor/dist cap to make sure they're in good shape. FWIW i replace my dist cap/rotor/wires/plugs all at the same time. stock gap os .054 but anything from .035-.054 should suffice.

-steve
 
5

5.0guy

Member
Apr 17, 2004
320
0
17
MI
Apr 19, 2004
#17
  • Apr 19, 2004
  • #17
my car is only rough when it's cold, it's alright when it's warm out.
 
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