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

need help on rough idle...did a bunch of tests...

  • Thread starter Thread starter killer5.0
  • Start date Start date May 3, 2010

killer5.0

5 Year Member
Oct 8, 2009
725
83
59
May 3, 2010
#1
  • May 3, 2010
  • #1
okay so i took it to my mechanic and he tested the TPS, AIC, ran the codes ...everything came back good...he had one code that was for a "flapper" on the stock airbox control i guess but said that since i have an aftermarket its not there and shouldnt affect it...he tuned the idle up a little which helps but its not a permanent fix he said...here is my list of mods and where should i go next? do i need a custom chip?

BBK headers, h-pipe to borla dumps (b4 rear axle)
BBK 70mm Throttle Body
BBK 70mm MAF
BBK CAI (fendermount)
3:73 gears
F303 cam
GT40 Upper and lower intake manifold
BBK FP regulator (at 38lbs at idle)
19lb injectors
200a alternator

thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 3, 2010
#2
  • May 3, 2010
  • #2
Find out what the actual code was.

If the idle itself is rough, like it misses, run a cylinder balance test.

Good luck.
 

killer5.0

5 Year Member
Oct 8, 2009
725
83
59
May 3, 2010
#3
  • May 3, 2010
  • #3
ill find out the code...definately isn't missing.
 

killer5.0

5 Year Member
Oct 8, 2009
725
83
59
May 3, 2010
#4
  • May 3, 2010
  • #4
codes thrown were...

21 (because it wasnt at operating temp at first but then he redid it with it at temp)

then it pulled
94 thermactor
44 thermactor...just want to verify what these codes are..
 

BigmacK192

New Member
Apr 8, 2009
210
0
0
Chicago.
May 3, 2010
#5
  • May 3, 2010
  • #5
Thermacore is the secondary air system (i.e. your smog pump and emissions controls). Are you running your smog pump still?
 

killer5.0

5 Year Member
Oct 8, 2009
725
83
59
May 3, 2010
#6
  • May 3, 2010
  • #6
the smog pump is currently hooked up but throwing air into the engine bay b/c i need to buy a shorter belt still...but i removed all the hardlines and vaccuum lines and plugged everything.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
May 4, 2010
#7
  • May 4, 2010
  • #7
If the smog pump is not dumping air into the exhaust system, then codes 94 and 44 will show.
 

killer5.0

5 Year Member
Oct 8, 2009
725
83
59
May 4, 2010
#8
  • May 4, 2010
  • #8
liljoe07 said:
If the smog pump is not dumping air into the exhaust system, then codes 94 and 44 will show.
Click to expand...

so nothing to worry about then...it cant affect performance correct?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
May 4, 2010
#9
  • May 4, 2010
  • #9
killer5.0 said:
so nothing to worry about then...it cant affect performance correct?
Click to expand...

Your fine, no different then any other Smog delete on these cars.
 
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