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89 5.0 running VERY rough

  • Thread starter Thread starter Josh40601
  • Start date Start date May 24, 2010
J

Josh40601

New Member
Apr 27, 2010
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San Diego/Frankfort, KY
May 24, 2010
#1
  • May 24, 2010
  • #1
Hello everyone, I have been trying to get my car to run, and run well for that late little bit, but seem to be failing horribly. I have set the timing in the car twice, all the wires are good, the plugs are good, and all the vaccum lines are connected. For some reason it is still having a hard time running. Once im driving, it is fine, but everytime i stop, it almost kills the car. When i first start the car, i have to hold the pedal down a bit to keep the car running. Anyone have a clue what is going on?
 

87GT Drop Top

Member
May 1, 2009
500
3
17
South Florida
May 24, 2010
#2
  • May 24, 2010
  • #2
Did you set the timing with the spout disconnected?
 
J

Josh40601

New Member
Apr 27, 2010
27
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San Diego/Frankfort, KY
May 24, 2010
#3
  • May 24, 2010
  • #3
spout?
 

RsStanG1987

I shaved all my pubes playing this game.
10 Year Member
Mar 13, 2004
569
9
79
Dupont PA
May 24, 2010
#4
  • May 24, 2010
  • #4
He means spout connector its the little black plug next to the dizzy. Has to be unplugged to set the timing.
 
J

Josh40601

New Member
Apr 27, 2010
27
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San Diego/Frankfort, KY
May 24, 2010
#5
  • May 24, 2010
  • #5
yes it was disconnected
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
May 24, 2010
#6
  • May 24, 2010
  • #6
What codes did you get?

Has the IAC been touched, cleaned or replaced? It affects the static and rolling idle.
 
J

Josh40601

New Member
Apr 27, 2010
27
0
0
San Diego/Frankfort, KY
May 25, 2010
#7
  • May 25, 2010
  • #7
the Check engine light doesnt come on. As far as the IAC, not too familiar, but if it is the Idle control, no it has not. I will check it and try to see if i can get some codes up
 
9

93GtMustang50

New Member
Jul 23, 2009
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0
Orlando
May 26, 2010
#8
  • May 26, 2010
  • #8
A new IACV and TPS will most likely suite you well. I replaced those on mine and It cleared out a lot of problems. Also make sure you check your fuel filter. A severely clogged fuel filter can cause all sorts of problems.
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
May 26, 2010
#9
  • May 26, 2010
  • #9
1st thing id do is remove the IAC, its on the side of the throttle, and clean it out very good, also id inspect the throttle body for gunk build up behind the butterfly, id also clean the mass air sensor. Ive found this to fix a lot of idle issues with the fox bodies
 
J

Josh40601

New Member
Apr 27, 2010
27
0
0
San Diego/Frankfort, KY
May 27, 2010
#10
  • May 27, 2010
  • #10
well guys, i got the IAC out, its literally BLACK on the inside of the intake and the IAC. I have some MAF cleaner im going to spray in there today. The TB is clean, that was the first thing i did when she was running rough and the MAF is brand new. I even used the MAF cleaner the day i installed the sensor. I'm going back to play with the car today, I'll post up what happens. Thanks so much guys for pointing me in a direction.
 
H

Haus

Member
Jul 20, 2005
408
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16
May 27, 2010
#11
  • May 27, 2010
  • #11
you may want to use like a carb or throttle body cleaner to clean the IAC
 
J

Josh40601

New Member
Apr 27, 2010
27
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0
San Diego/Frankfort, KY
May 27, 2010
#12
  • May 27, 2010
  • #12
Amazon.com: CRC 05110 Mass Air Flow Sensor Cleaner - 11 Wt Oz.:…

This is what i have
 
H

Haus

Member
Jul 20, 2005
408
0
16
May 27, 2010
#13
  • May 27, 2010
  • #13
Josh40601 said:
Amazon.com: CRC 05110 Mass Air Flow Sensor Cleaner - 11 Wt Oz.:…

This is what i have
Click to expand...

i have that too but I use it on my MAF Sensor wires

not sure thats going to dissolve all of the black **** in your IAC

you should get a can of carb, throttle body cleaner to spray into the holes and maybe a q tip to get any extra build up that wont dissolve
 
J

Josh40601

New Member
Apr 27, 2010
27
0
0
San Diego/Frankfort, KY
May 27, 2010
#14
  • May 27, 2010
  • #14
awesome. I just tried it, and it got some of the stuff off, I am going to swing by the parts house today and grab a can of TB cleaner. I'll let you know if it works!
 
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