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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Could the Underdrives Cuase This?????(i am confused)

  • Thread starter Thread starter bryce93lx
  • Start date Start date Aug 5, 2006

bryce93lx

Member
Jan 20, 2006
88
1
19
Luke AFB AZ
Aug 5, 2006
#1
  • Aug 5, 2006
  • #1
Okay this does not make any freakin sense to me so maybe it does to someone else, i

did a h/c/i a while ago, dart pro 1 heads, cobra intake a e303 a 65mm bbk throttle body

and 73mm c&l mass air, calibrated to the 24 pounders, the thing runs great and has had

no problems, unless the weather is very humid then it would load up idle rough and pop

and miss when i took off the first time, then it would clean out and run, also several

times it acted as if flooded and would not run, it had tons of soot in the exaust tips

indicating it is rich, i though is was a issue of timing, or the c&l was funky, i switced from

92 to 87 octane to see if it was getting to much fuel(lower octane would lean it out) and

it ran better, but we got a few hot days and i switched back to 92 and the night driving

the problems persisted. Well yester day i was tinkering with the car and switched back

to the stock crank pulley mostly becuase of cooling and charging issues. Now the car

runs a 100xs better, it always hesitated off the bottom, which i though was the stock

stall, now it runs better down low, idles better, and is faster(sop, scale anyways) so

what the hell???? it is friggin raining right now and the car runs fine, better than ever. I

have two 600 watt amps and another smaller one, coule the electrical system have been

taxed and the meters have low power and sending bad signals???? or the comp low on

power, i would think with a 12v system it either works or does not right???

i do not under stand what is going on, nothing else changed at all, what could this all

mean, sorry for the novel, anyone shine some light on this???

confused in stangland
 

68torinogt

Hey guys, guess what--I have a bi-pass!!!
Mar 21, 2006
0
0
53
Welcome my son, welcome to the machine
Aug 5, 2006
#2
  • Aug 5, 2006
  • #2
too long it needs to have spaces every few lines
 

bill302

Active Member
Nov 2, 2005
2,131
1
46
alabama,gadsden
Aug 5, 2006
#3
  • Aug 5, 2006
  • #3
i had similar problems with my underdrives and i cleared up the problem by installing the stock alternator pulley and i also had to clear the computer,then crank engine with the iac disconnected turn idle screw and set idle at 850-900 rpms, turn the car off then i reconnected the iac and cranked engine with the lights,a/c and radio with amp turned on for a few minutes, then i turned engine off and set the tps at .99 and drove for about 15 mins this fixed my problem. the best way to tell if you have charging issues at idle is to run all accessarys and check voltage at the battery if it falls under 12 volts you have problems...
 

bryce93lx

Member
Jan 20, 2006
88
1
19
Luke AFB AZ
Aug 5, 2006
#4
  • Aug 5, 2006
  • #4
so i am not crazy then well that's a good sign
 

bill302

Active Member
Nov 2, 2005
2,131
1
46
alabama,gadsden
Aug 5, 2006
#5
  • Aug 5, 2006
  • #5
bryce93lx said:
so i am not crazy then well that's a good sign
Click to expand...
no your not crazy you fixed yours by reinstalling the old pulleys but i sold my old pulleys and had to figure a way to run in the heat with the underdrives so i reinstalled a factory alt. pulley and idled the engine up and allowed the computer to relearn and this worked for me before i installed factory alt pulley and reset idle and computer i could not idle and run the a/c by itself without having problems with the motor running hot and rough..
 

68torinogt

Hey guys, guess what--I have a bi-pass!!!
Mar 21, 2006
0
0
53
Welcome my son, welcome to the machine
Aug 6, 2006
#6
  • Aug 6, 2006
  • #6
thanks for making it easy to read it seems to run together after it gets to be a certian length
 
S

superhuaman

New Member
Nov 8, 2004
907
0
0
Harrisburg, PA
Aug 6, 2006
#7
  • Aug 6, 2006
  • #7
If your voltage drops below a certain point, the computer will try to compensate for low injector voltage by increasing pulse width. This is done so the engine doesnt run lean. So that is why your engine was pigging out.
 
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