Idle issue still!! Replaced several parts.. looking for more ideas!!

Joshmack111

Member
May 28, 2020
19
2
13
35
Raleigh, nc
Alright guys 93 5.0 high hanging idle and no power very sluggish... I've replaced the egr valve, and the idle air control, and checked the voltage on the tps and adjusted it lower at .96 now. Also checked the fuel pressure while off key in on position was at 35. Havnt done it while running yet. Built a smoke tester and didn't see any vacuum leaks accept for the egr before I replaced it. About to go crazy over here. What else should I be looking for. Maybe a vacuum leak somewhere else? Any ideas please.
 
Last edited:
  • Sponsors(?)


KRUISR

Active Member
Apr 16, 2015
259
82
38
50
Some other info on the engine combo. Is this totally stock or heavily modified? If modified, with what?
 

CarMichael Angelo

clearly, I’ve got something going on in that hole
SN Certified Technician
Nov 29, 1999
12,915
14,159
234
62
Birmingham, al
m.imdb.com
I cant tell you how to fix it, but Its spelled " idle" .
Start there, and maybe the "over 10th graders" will chime in to help.
 

Joshmack111

Member
May 28, 2020
19
2
13
35
Raleigh, nc
Just bolt on stuff nothing major. Bbk 70mm throttle body, mass air meter, cold air intake. That's mainly it for the engine. Car has been sitting up for a while. Has fairly new plugs and wires. Been trying to get it back on the road. Cranks up no problem immediately goes to about 1500 rpms the after about a minute comes down to 1100. Never gets below that while just idling. If I drive it doesn't want to get below 2000. And feels down right slow..
 

redNfast

Active Member
Apr 5, 2020
67
29
28
74
Woodstock, GA
Just bolt on stuff nothing major. Bbk 70mm throttle body, mass air meter, cold air intake. That's mainly it for the engine. Car has been sitting up for a while. Has fairly new plugs and wires. Been trying to get it back on the road. Cranks up no problem immediately goes to about 1500 rpms the after about a minute comes down to 1100. Never gets below that while just idling. If I drive it doesn't want to get below 2000. And feels down right slow..

Are the parts matched or cherry picked here and there?

70mm throttle body that stock or go fast........er + " mass air meter, cold air intake" .......... might need a soft tune to make things work.

Computer managed engine controls are unlike the carb days. More demanding, mapping is precise .

Tried grabbing any codes from it?
 
Last edited:

Joshmack111

Member
May 28, 2020
19
2
13
35
Raleigh, nc
No nothing cherry picked I've had the car for about 17 years I know all the parts that have been replaced, I did pull the codes and all it gave me was low voltage to the tps sensor I believe it was 63. Cant remember now. When I checked the voltage it was high, so I adjusted it down to about .96
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
17,302
5,591
193
polk county florida
Start here:
Read it through, make sure you understand then start at the top and do it step by step, don't skip around.
You to be methodical when it comes to efi.
No, you do not need a 'soft tune'.
Maybe a 'tune up', but not a 'tune'.
 
  • Like
Reactions: nickyb

nickyb

WAIT,you now have a pair?
5 Year Member
Apr 3, 2009
312
116
63
57
nevada
Start here:
Read it through, make sure you understand then start at the top and do it step by step, don't skip around.
You to be methodical when it comes to efi.
No, you do not need a 'soft tune'.
Maybe a 'tune up', but not a 'tune'.
Agreed!
 

redNfast

Active Member
Apr 5, 2020
67
29
28
74
Woodstock, GA
Start here:
Read it through, make sure you understand then start at the top and do it step by step, don't skip around.
You to be methodical when it comes to efi.
No, you do not need a 'soft tune'.
Maybe a 'tune up', but not a 'tune'.
I agree no soft tune stock parts, my mind thinks modified most times.
 
Thread starter Similar threads Forum Replies Date
aah86mustang Still Having Idle And Drivability Issues Fox 5.0 Mustang Tech 7
E Idle issue still going on....... Fox 5.0 Mustang Tech 6
lead09 Help! I've done the checklist and still having idles issues, s/c, cai and maf... Fox 5.0 Mustang Tech 1
0 4.6 2v SOHC 2k rpm Idle, help reading engine data SN95 4.6L Mustang Tech 0
R Engine Remove the Idiot from the equation. Idle/hesitation issue. Fox 5.0 Mustang Tech 3
C 2014 Mustang Gt/Cs Idle and dying issue 2010 - 2014 Specific Tech 2
C Engine Gray smoke from exhaust. Smells like gas. Fox 5.0 Mustang Tech 15
S Another Idle surge post with microsquirt Digital Self-tuning Forum 5
A New fox owner, idle issues need some advice Fox 5.0 Mustang Tech 20
J 2000 GT Idle/Running Issues SN95 4.6L Mustang Tech 6
B Slight surging idle issues Digital Self-tuning Forum 14
S Megasquirt PNP2 460SBF startup/idle issues Digital Self-tuning Forum 9
F Idle Fluctuation Issue 98 GT SN95 4.6L Mustang Tech 0
D Engine Idle issues Fox 5.0 Mustang Tech 23
T 91 mustang idle surging Fox 5.0 Mustang Tech 5
Xenogenesis Timing issue at idle SN95 V6 Mustang Tech 1
justinmurray2001 idling issues SN95 4.6L Mustang Tech 6
F Water pump issue at idle Fox 5.0 Mustang Tech 17
S Megasquirt pnp idle issues Digital Self-tuning Forum 19
L At my wits end...96 Cobra idle and other issues... 1996 - 2004 SN95 Mustang -General/Talk- 3
S Idle issues, missfire, backfire, stalling 1994 - 1995 Specific Tech 29
9 MS2 Cold Start Issues Digital Self-tuning Forum 6
Nightstang00 Idle issues with a foxbody and microsquirt Digital Self-tuning Forum 31
V Exhaust AEM AFR no reading at idle Placement issue ? Fox 5.0 Mustang Tech 4
Joe Medeiros Idling issues 1965 - 1973 Classic Mustangs -General/Talk- 2
O Engine Code 12, 92; Code 12 will not go away! Fox 5.0 Mustang Tech 25
Onesick99GT Low rpm stalling fix 1996 - 2004 SN95 Mustang -General/Talk- 0
Onesick99GT Speedometer Not Working Fix SN95 4.6L Mustang Tech 0
S Idle problem 1990 with gt40 crate engine 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 1
C Idle Hanging (Solved) and stupidly simple. 1996 - 2004 SN95 Mustang -General/Talk- 2
M Weird Idle/Power Issue SN95 V6 Mustang Tech 1
Dustin2v Engine Please help! Issues starting, running, idling SN95 4.6L Mustang Tech 4
M 1994 Ford Mustang GT 5.0 idle issues Fox 5.0 Mustang Tech 1
L Engine Rough Idle at Start, Possible CMCV Vacuum Leak 2015+ Specific Tech 0
C Stalling and idle issues 2005 - 2014 S-197 Mustang -General/Talk- 3
S 08 GT idle/emission issue 2005 - 2014 S-197 Mustang -General/Talk- 1
S Engine 2000 Mustang Idle issue SN95 V6 Mustang Tech 1
Cnorth94 BBK throttlebody/plenum combo idle issues 1996 - 2004 SN95 Mustang -General/Talk- 0
N Engine 1987 LX 5.0 5 Speed - idle and . . . Fox 5.0 Mustang Tech 4
Onesick99GT 99 Mustang GT High Rev On Cold Start SN95 4.6L Mustang Tech 25
N 95 convertible idle issues stange power surges 1994 - 1995 Specific Tech 6
N 98 Mustang GT will not idle 1996 - 2004 SN95 Mustang -General/Talk- 7
N Car doesn’t want to idle anymore after supercharger install 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 17
C Engine 1988 gt high idle and throttle issue. Fox 5.0 Mustang Tech 3
B Engine 1998 GT - Weird idle and misfire issues SN95 4.6L Mustang Tech 6
M 1994 Mustang GT 5.0HO - Idle issue - Seeking advice Fox 5.0 Mustang Tech 6
H 03 4.6 SN95 Idle issues 1996 - 2004 SN95 Mustang -General/Talk- 2
B 2002 GT bad TPS values and idle issues 1996 - 2004 SN95 Mustang -General/Talk- 4
A Engine 94 gt 5.0 sporadic idle issues 1994 - 1995 Specific Tech 4
M High idle, big mystery 1996 - 2004 SN95 Mustang -General/Talk- 3
Similar threads