• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

tweecer/tuner guys...need some quick help

  • Thread starter Thread starter HazMat404
  • Start date Start date Nov 19, 2004
H

HazMat404

Founding Member
May 24, 2002
1,749
0
36
Nov 19, 2004
#1
  • Nov 19, 2004
  • #1
alright, well i decided that my cold startup problem (backfire, chugs and whatnot) has to do with being super rich at startup. is there a way to lean out my car at startup because whenever its cold, i always have problems of my car dying on me and backfires and whatnot. i think she might be running to rich at idle in general. is there an semi easy fix with this with the tweecer or will it take me awhile to screw around with tables?? if i could just knock off like a .1 on a table to lean me out, that would be perfect. any help would be great. thanx
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Nov 19, 2004
#2
  • Nov 19, 2004
  • #2
Brad

If you are too rich at idle under normal conditions then yes, you would be a good bit richer when stone cold.

When using larger inj's this is not uncommon but I don't see that you have them. I gotta think if you find why you are too rich the cold starts will fall in place.

A few Q's & thoughts about your rich idle.

Have you loaded the ProM bullit curve values in your cal file?

At normal temps do you have a idle that surges?

What do your K's look like at idle?

Your cai could have messed up your first few low maf points cause I've changed my cai a couple of times and each time I had to do a little tweecing to get back a steady idle.

The fuel_table_startup_OL is where you make changes for larger inj's. Before I give you my changes you need to know that since you live in Yankee Land you have to deal with much colder temps than I do. I've heard some say that if you go too lean tha car might not start when the temps really drop.

Just noticed you don't say if you are using t4m0 or j4j1.

My j4j1 table looks like this:

All values in all cells are stock except ... all cells have the value of 0 in time rows 60 & 80.

The same goes for ECT columns 210 & 240.

Later
Grady
 
H

HazMat404

Founding Member
May 24, 2002
1,749
0
36
Nov 19, 2004
#3
  • Nov 19, 2004
  • #3
awesome...thanx for the help. ill try to keep it simple. im using the stock t4m0 tune right now. there is only a few changes im using to it. i dont have the pro-m 75mm maf table cause i can never find it. tried a few times. im pretty much stupid in terms of K's and whatnot. i can do a test and see what they are but i have no idea what they mean cause i havent done my homework on this tweecer yet. i still have the stock 19# injectors with a 19# injector. i pretty much just wanted to lean out my startup for a few min then after that go back to normal. ifyou can gimme a few numbers that might be able to lean me out just a bit, that would great....thanx a ton
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Nov 19, 2004
#4
  • Nov 19, 2004
  • #4
HazMat404 said:
if you can gimme a few numbers that might be able to lean me out just a bit, that would great....thanx a ton
Click to expand...

The fuel_table_startup_OL is where you make changes

All values in all cells are stock except ... all cells have the value of 0 in time rows 60 & 80.

The same goes for ECT columns 210 & 240.

Later
Grady
 
H

HazMat404

Founding Member
May 24, 2002
1,749
0
36
Nov 20, 2004
#5
  • Nov 20, 2004
  • #5
alright...im kinda stupid with this tweecer still. she is definately pig rich at idle even with my f/p at 37 (vac off). what should i start to lower? detailed instructions would be great
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Nov 21, 2004
#6
  • Nov 21, 2004
  • #6
HazMat404 said:
alright...im kinda stupid with this tweecer still. she is definately pig rich at idle even with my f/p at 37 (vac off). what should i start to lower? detailed instructions would be great
Click to expand...

Brad

Looked over your combo again and with the e-cam you might have a challenge on your hands. That cam and bad idle seem to go hand in hand as I've seen on the various forums. I also know there are guys on the Tweecer forums that got them to idle pretty good.

I'll try to help you but a little research on your part will give you an idea of what is (or not) going on with your idle from the pcm's point of view.

Go over to the Tweecer site and search out the idle threads on OUR, not fox body pcm's, CABZA family only (t4m0 & j4j1). Download the EEC Analyzer to read the help files on the tab called TB Air Flow & ISC. The program is very helpful. If you decide to use it there is a fee but you can use the help files for your research now and pay later if you choose to.

1. Put your fuel pressure back to stock and leave it there cause any fuel changes you make will go out the window if you then mechanically change it.

2. Answer these Q's for me please!

What makes you think rich instead of lean?

Have you loaded the ProM bullit curve values in your cal file?

At normal temps do you have a idle that surges?

What do your KAMRF's look like at idle?

That outta keep you busy for a while

Later
Grady
 
H

HazMat404

Founding Member
May 24, 2002
1,749
0
36
Nov 21, 2004
#7
  • Nov 21, 2004
  • #7
well right away i can smell the richness. ive always known what rich smells like and its definately rich.

ive tried finding the pro-m maf curve but could never find it.

it idles perfectly fine once warm but still smells rich at idle.

i havent datalogged yet cause i never really got into the tweecer too much. just barely scratched the surface.


i will put the f/p back to stock (thats 38 psi right?) and leave here there for now and i will try to figure how what my kamrf is within the next day or two whenever i have a free moment. i will make my way over to the tweecer website at work today if its slow enough.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Nov 21, 2004
#8
  • Nov 21, 2004
  • #8
HazMat404 said:
well right away i can smell the richness. ive always known what rich smells like and its definately rich.
Click to expand...

OK, we'll go with that assumption

ive tried finding the pro-m maf curve but could never find it.
Click to expand...

No prob ... You've had it all the time but just didn't know it

You can use Cal Edit to load in the curve but you have to use this method.
http://tweecer.oplnk.net/viewtopic.php?t=1449&highlight=bullet

it idles perfectly fine once warm but still smells rich at idle.
Click to expand...

OK, After we get the bullet curve loaded in the cal file we will go from there.

i havent datalogged yet cause i never really got into the tweecer too much. just barely scratched the surface.
Click to expand...

Well .... I guess your getting into it now

When you are able to datalog and see what the KAMRF's are doing here is what we want to do to get the data we need to know. Have paper/pen, Cal Con digital display showing KAMRF's for both sides and drive around until you get to normal temp. Pull in a parking lot or somewhere you can sit and idle for about five mins without killing the motor. Write down the values at the start, then at 1 min, 2 min, etc until the 5 mins have expired. We are looking for a trend of the data that will be steady, rise or falling K's. 1.0 = perfect ... less than 1.0 = rich ... more than 1.0 = lean

i will put the f/p back to stock (thats 38 psi right?) and leave here there for now and i will try to figure how what my kamrf is within the next day or two whenever i have a free moment. i will make my way over to the tweecer website at work today if its slow enough.
Click to expand...

Thats Great

Brad

This is the MOST important thing for you to know ............................

If any of this stuff gives you cause for concern or anything like that ... Don't do anything with the maf transfer curve. Just get to the point that you are comfortable with simple changes like changing your idle speed and saving it to a new cal file so you can upload it to the Tweecer. Building a payload of variables like spark, rpm, mph, kamrf, etc in Cal Edit so that it will show up in Cal Con's display would be the next basic thing for you to be able to do.

Master the stuff in the above paragraph you'll think your a
TUNING GURU

Later
Grady
 
You must log in or register to reply here.

Similar threads

S
Fuel ‘88 GT Runs Rich Cold — Fixes Itself When I Unplug Sensors (ECT, MAF, O2, etc.)
  • Sufarry
  • Nov 6, 2025
  • Fox 5.0 Mustang Tech
Replies
12
Views
740
Fox 5.0 Mustang Tech Nov 9, 2025
Mustang5L5
1999 Mustang GT - No Start- Need help understanding the fuel pump circuit and how it works
  • 99gtGuy
  • Nov 4, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
1
Views
481
1996 - 2004 SN95 Mustang -General/Talk- Nov 7, 2025
04newedge-
0
M
Engine Unexplainable Exhaust Pop and Gurgle
  • Mrnissen122
  • Feb 14, 2026
  • Fox 5.0 Mustang Tech
Replies
12
Views
483
Fox 5.0 Mustang Tech Feb 18, 2026
Noobz347
Progress Thread Progress Thread- From6to8's 95 GT/Saleen Supercharged 331 install
  • from6to8
  • Mar 22, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
24
Views
729
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 6, 2026
from6to8
Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?