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

Solve my CPU mystery!

  • Thread starter Thread starter h0oligan
  • Start date Start date Oct 13, 2004

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 13, 2004
#1
  • Oct 13, 2004
  • #1
Alright, it all started when I put on my ebay CAI. Now my check engine light comes on after I drive for like 3 minutes. So, i couldn't figure out what the problem was so I decided to go to the local Autozone/advanced and have them read the codes with their machine so I could figure out what was wrong. However, when they looked up my car in the computer, which is a 94 GT, it said that they should have to plug the reader in inside the engine bay, but there isn't anything there (unless we just didnt see it). I do have a plug underneath the driver's side dash which appears to be OBD2, but the people at ford and autozone said that this would be impossible; that they didn't make these in 94. Anyway, so we tried plugging in the reader into the plug under the dash and it had link errors meaning it didn't work. I went to ford to have them help me figure it out, but they wouldn't even look at it without 75 bucks; I now turn to trusted STANGNET. So, what's the deal here? Is there a plug inside the engine bay that I didn't see? Why did my CAI set off the check engine light? How can i fix this??? HELP ME
 

stang976

New Member
Apr 13, 2004
853
0
0
Westchester, NY
Oct 13, 2004
#2
  • Oct 13, 2004
  • #2
is the car running fine??


what code was pulled??


did you tamper with the MAF sensor when reinstalling??
 

Chythar

Recently finished repairing my rear
20+ Year Stangneter
Aug 26, 2004
2,373
140
113
Foothill Ranch, CA
Oct 13, 2004
#3
  • Oct 13, 2004
  • #3
94-95 GT are OBD1; 94-95 V6 are OBD2

I understand the connector is there becuase the dashboard is shared between the V6 and GT. Basically, it's cheaper to leave the OBD2 connector there than to remove it. But it doesn't work on the GT.

I don't know how to pull the codes for the GT either, so I can't help you there. Have you used the forum Search feature? I'm sure someone's already asked a similar question.
 
M

mackey

Active Member
Jan 25, 2003
1,284
1
38
Beverly, Massachusetts
Oct 13, 2004
#4
  • Oct 13, 2004
  • #4
Gotta pull the codes manually using the check engine light...
 

dstanggt50

Founding Member
Sep 13, 2000
1,316
0
0
Woodinville, WA
Oct 13, 2004
#5
  • Oct 13, 2004
  • #5
My connector is by the passenger side firewall. There are 2 connectors that you plug into your scan tool. I never looked for a connector in the car before. Chk by the firewall.
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 13, 2004
#6
  • Oct 13, 2004
  • #6
my guess is you have a vacuum leak and the you are running lean. does it ping now when you step on it?
 

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 13, 2004
#7
  • Oct 13, 2004
  • #7
It isn't running too bad, i think. I've never heard or felt pinging so I don't know what it's like. Is it something i would obviously notice? I do think it is running a little lean though, because sometimes at idle right after i start it up it wants to die, but that's not too often. Either way, does anyone else have any other ideas? I'll check out some more tmrw.
 

go-stang5.0

New Member
Jan 27, 2003
2,244
0
0
Glenview,Il
Oct 13, 2004
#8
  • Oct 13, 2004
  • #8
Yes the connector is by the firewall on the passenger side. If I remember correctly it has a rep plastic cover on the plug. THe plug is like 2cmX1cm so its kinds big. It shouldent be hard to find.
 

TrueBlue95GT

Member
Sep 29, 2003
966
0
16
Connecticut
Oct 13, 2004
#9
  • Oct 13, 2004
  • #9
You can check the codes yourself if you have a voltmeter and a couple of wires. The positive from the voltmeter goes to the positive on the battery. The negative goes to the pin in the harness that is 2nd from the left in the row with 4 pins if it is on bottom. Then you put another wire from the 2nd pin from the left in the row with 2 pins and put the other end of that wire into the other dangling connector. Then you turn the car to the ON position but dont start it up. The check engine light will bleep once and then go through the codes. The number of times the light flashes is a number and it waits like 2 seconds between numbers and 4 seconds between codes. Write them all down and come back to me with the codes and I can tell you what they mean. This is all from the Haynes Manual, which is a good investment.
 

94CobraPace

Founding Member
Aug 30, 2000
907
1
0
Houston, Tx.
Oct 13, 2004
#10
  • Oct 13, 2004
  • #10
On the passenger side fender well on the back side. It could be down some, but it is there. You can get a code reader from Walmart or Autozone for less than $30.
Did the CAI have a oiled filter? Could have been over oiled. Might want to try and clock the MAF meter, they don't like turbulance from the bend in the CAI.
 

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 14, 2004
#11
  • Oct 14, 2004
  • #11
alright, thanks for the info. I'll check out the haynes manual this week, i didn't even think of looking in there for some reason. After I check the codes, what do you think it's gonna tell me and how should i go about fixing the problem? I don't think that the filter is an oiled filter, (not sure how to tell). I had a k&n before though, and that's oiled right? Anyway, thanks again, I'll already learned a lot.
 

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 19, 2004
#12
  • Oct 19, 2004
  • #12
Alright, I found the plug (easily) and went to advanced again to have him pull the codes cuz I'm too lazy to do it myself. This guy knew what he was doing and already knew that it was in the engine bay. So, after he did it and printed out the codes, it said "KOEO Code 0 No Definition Available." He didn't know what to tell me. Now what should I do I'm stumped. I want to avoid paying the 75 bucks to have ford look at it. HELP


94CobraPace said:
Did the CAI have a oiled filter? Could have been over oiled. Might want to try and clock the MAF meter, they don't like turbulance from the bend in the CAI.
Click to expand...

How do I clock the MAF meter?
 

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 20, 2004
#13
  • Oct 20, 2004
  • #13
anyone?
 

blksn955.o

Founding Member
Mar 15, 2002
3,263
0
66
st.louis mo 314
Oct 20, 2004
#14
  • Oct 20, 2004
  • #14
clocking the meter is the rotating of the meter (in its mounting area) a few * at at time to see if the CAI is messing up the air flow, this is common that the CAI causes turb. in areas and the meter tube gets a false reading.

KOEO means Key Off, Engine Off, (I think) the other is R for O which means Running there was no signal due to no power on the system, there should be a label on the code reader that tells you if you need it key in or on and engine on or off. I may be backward, since I get the on/running mixed up.
 

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 20, 2004
#15
  • Oct 20, 2004
  • #15
I could see that, but the light doesn't come on until i get up to about 50mph and cruise there for a little. After that though it just stays on until i shut the car off. I hope i don't have a cpu problem though since the codes can't be pulled.
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 20, 2004
#16
  • Oct 20, 2004
  • #16
i'm still voting that you have a vaccuum leak somewhere and that the light is for a too lean condition. i really doubt your computer is bad. did you try putting the stock stuff back on and seeing if the problem goes away?

when i had a vac leak, the light wouldn't come on until i was on the highway and i was turning about 2500 or so. even then sometimes it wouldn't come on unless i stepped on it.

try getting some carb cleaner and, with the engine idling, spray around the hose connections and different areas around the intake track. if the idle changes when you spray something, that is where the leak is.

mine turned out to be that a little plug on my PCV valve got knocked off when i was installing the mass air meter housing.

- chris
 

94CobraPace

Founding Member
Aug 30, 2000
907
1
0
Houston, Tx.
Oct 20, 2004
#17
  • Oct 20, 2004
  • #17
Try clocking the maf meter to see if that helps. Might need to clean your MAF sensor wire, new oiled filters seem to always have too much oil on them.
If not, how old are you O2 sensors?
 

h0oligan

New Member
Jan 18, 2003
271
0
0
Oct 20, 2004
#18
  • Oct 20, 2004
  • #18
I would be willing to bet that my O2 sensors are the age of the car, so about 10yrs.
 
You must log in or register to reply here.

Similar threads

S
Electrical No dash lights
  • slojoexxx
  • Dec 11, 2025
  • 1994 - 1995 Specific Tech
Replies
0
Views
133
1994 - 1995 Specific Tech Dec 11, 2025
slojoexxx
S
L
95 gt engine vibration
  • lenzgt
  • May 11, 2026
  • 1994 - 1995 Specific Tech
Replies
6
Views
152
1994 - 1995 Specific Tech May 26, 2026
lenzgt
L
D
Electrical/engine bay harness questions
  • djj62478
  • May 29, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
7
Views
174
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 6, 2026
djj62478
D
W
Megasquirt base tune for 94 5.0
  • wrx757
  • Mar 6, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
3
Views
178
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Mar 6, 2026
wrx757
W
K
Electrical 2000 GT Intermittent Engine Shutdown In Motion - DTC U1262
  • kenster1092
  • Apr 13, 2026
  • SN95 4.6L Mustang Tech
Replies
4
Views
158
SN95 4.6L Mustang Tech Apr 24, 2026
squeak93
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?