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

New PMS...idle problems-bad!

  • Thread starter Thread starter txstang84
  • Start date Start date Nov 6, 2006

txstang84

15 Year Member
May 21, 2005
1,639
42
69
Tuscola, tx
Nov 6, 2006
#1
  • Nov 6, 2006
  • #1
I just got my PMS in the mail today (series II), and tried to hook it up...after zeroing out the previous owners info, I finally got it to start (previous settings had like -68% on startup fuel)...this thing would not idle anywhere below 1500, and it takes a while to settle down to that from 2000 when it first starts...I tried to lean it out a little, i tried pulling timing, i tried slowing down the IAC, I didn't get a chance to lean out the cold comp before it overheated (due to my stupidity-I disconnected my electric fan when I zeroed out the settings, and forgot to reconnect it.)

any help here would be greatly appreciated. From what I understand my C&L is probably part if not all of my problem, but I talked to Rick at AFM and he said that while it may be a PITA to tune around, it is possible. Anybody got any ideas?

I followed the instructions on the AFM website for setting the TPS to idle, I set the idle @ 900rpm (IAC disc) and after I was done, the handheld showed idle...it started off before showing "Idle: Pr L." Anyway, I'm scratching my head on this one, I zeroed everything out that I could before puking my radiator all over the garage (so much fun).

For the time being, I disconnected it, so I can still make it to and from work...guess it'll have to wait till this weekend.

Thanks in advance guys...


Year model: 1984
Engine cubic inch: 302
Power Adder/NA: NA
Amount of boost/nitrous:
Intake: cobra
Throttle Body: 70mm
Mass Air Meter: 73mm C&L
Intake Piping: cold air
Cylinder Head & rockers: GT-40 + stock '95 Cobra rockers
Camshaft profile: lunati 51014 284/292 total; 218/226 @ 050; 0.500/ 0.510"
Injector Size: 19
FMU type: N/A
Header size/type: 1 5/8 Mac longtube
Fuel Pump(s): 155
Rails: stock
Supply/Return Line size: stock
Fuel type: 91 oct

IDLE Control On/Off:
fuel:
timing:
start-up fuel:
idle air adjuster:
Low Load (Fuel first & Timing second)
2200rpm:
4000rpm:
6000rpm:
7800rpm:
Medium Load (Fuel first & Timing second)
2200rpm:
4000rpm:
6000rpm:
7800rpm:
High Load (Fuel first & Timing second)
2200rpm:
4000rpm:
6000rpm:
7800rpm:
WOT (Fuel first & Timing second)
2200rpm:
4000rpm:
6000rpm:
7800rpm:
Boost or Tables: (Fuel first & Timing second)
Max Boost setting:
@1 psi
2200rpm:
4000rpm:
6000rpm:
7800rpm:
max Boost
2200rpm:
4000rpm:
6000rpm:
7800rpm:
Nitrous Tables: (Fuel first & Timing second)
N20 on
2200rpm:
4000rpm:
6000rpm:
7800rpm:
Standalone On/Off:
Rev Limiter
 

txstang84

15 Year Member
May 21, 2005
1,639
42
69
Tuscola, tx
Nov 7, 2006
#2
  • Nov 7, 2006
  • #2
disregard all...I had idle control turned on during tuning, Rick at AFM informed me that they are informing people to get away from that, so...should be good now
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Nov 7, 2006
#3
  • Nov 7, 2006
  • #3
I was gonna post that last night to make sure its off! I shoulda posted..lol
 

txstang84

15 Year Member
May 21, 2005
1,639
42
69
Tuscola, tx
Nov 7, 2006
#4
  • Nov 7, 2006
  • #4
no worries bro, I got it squared away, and the cold comp worked 18% cleared it right up-now, I can play with other things!
 

DigitalGhost

New Member
Nov 10, 2006
18
2
0
Portland, OR
Nov 11, 2006
#5
  • Nov 11, 2006
  • #5
speaking of idling problems, my stock 1990 has been idling at anywhere from 1500 to 2000 off and on. Sometimes it idles that high, sometimes it goes back to normal (under 1k.)

Anyone know what causes that on a stock 5.0 engine and how to fix it?
 

LtDavis

20+ Year Stangneter
Nov 19, 2004
75
2
19
Raleigh, NC
Nov 11, 2006
#6
  • Nov 11, 2006
  • #6
Digital Ghost- I was having idle trouble on mine and replaced the IAC with a 60 dollar NAPA piece. Fixed the idle
 
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