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New motor-won't run right. horribly rich

  • Thread starter Thread starter espv-250
  • Start date Start date Apr 8, 2005
E

espv-250

Founding Member
Jun 24, 2002
66
0
0
Apr 8, 2005
#1
  • Apr 8, 2005
  • #1
Just threw a new motor in my car. not completely new-bottom end rebuilt recently, stock heads, i think stock cam, 1.6 rollers, stock intake, 65mm tb/egr spacer, stock maf, mac headers, o/r h, flows. The car won't idle when cold, and won't idle correctly when warm. When warm, if car is shut off and started, idle is correct for about 15s, then goes low and poor. when engine is loaded (drive) it sounds like horribly bad timing, misfiring almost, like an old truck, but timing seems fine when I time it. Also, the fuel pressure is dead at 38 psi, but the car is so rich that after a few breaths 20ft near the back of the car my eyes burn horribly (and im used to being around rich cars). The thermactor system is not hooked up, but other than that, everythings good. No codes are being thrown (at least no check engine light). Any ideas, i need help bad. ---thanx

~John~
 
D

Daggar

New Member
Jul 19, 2004
3,902
5
0
Apr 8, 2005
#2
  • Apr 8, 2005
  • #2
It sounds as if you've got vaccum lines either open or incorrectly fed.

Go back and pull codes. The only thing the check engine light is good for on Mustangs is to tell you that's it's too late.
 

LX302

Stanger
Founding Member
Feb 29, 2000
728
6
19
Bethlehem PA
Apr 8, 2005
#3
  • Apr 8, 2005
  • #3
Did you set up (correct voltage) on the TPS on the throttle body?
Check the timing?
Check the spark plug wire order?
Just some things to llok at.
 
E

espv-250

Founding Member
Jun 24, 2002
66
0
0
Apr 8, 2005
#4
  • Apr 8, 2005
  • #4
checked vacuum lines, alls good, timings right, voltage on tps good, won't throw codes. Im using a little hand-held code retriever, should I use something else. Im thinkin weak ignition. Don't know why, just a hunch. Im gonna throw new o2's, ignition module, and msd coil at it and see what happens, any other ideas?. thanx guys, appreciate the help.
 

feifong

New Member
Apr 4, 2005
319
0
0
mesa
Apr 8, 2005
#5
  • Apr 8, 2005
  • #5
check the m.a.p sensor hoses or see if u can replace it 4 cheap
 
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