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

Engine light gremlin....

  • Thread starter Thread starter Lynkx
  • Start date Start date Mar 3, 2004

Lynkx

Founding Member
Jul 31, 2001
371
0
0
Vancouver Island BC
Mar 3, 2004
#1
  • Mar 3, 2004
  • #1
New flowmasters. while installing we cut a set of cats, and installed 2 new O sensors.

Now it ran fine, all good.

I just got my heatercore fixed today, and the engine light is on.

So i checked fluid level, and right now oil is really high for some reason??? When the car cools, the oil goes down to normal.
After being ran it still rises back up. (i might be just paranoid since the light is on.) Common sense tells me when i check oil right after its shut off after running for 5 mins the oil is high just from the engine sloshing it around

Checked all caps, listened for odd noises. car runs smooth, nice.. so my guess is the cats being cut confused the computer.

Any idea's?

Last thing im going to do is just pop the engine cap and check for air in the system for some odd reason, and after that pull off the battery cables and wait a few minutes for the computer to reset itself.

Hope nothing pops up during the drive from sooke to cobble hill. Thanks for replies.
 
L

leakyfaucet

Member
Dec 19, 2003
273
0
16
North Carolina
Mar 3, 2004
#2
  • Mar 3, 2004
  • #2
By cutting the cats do you mean taking them off and replacing them with a pipe or do you mean gutting them? The computer should have no idea that you've done that. I think 94+ had 02 sensors behind the cats though.
 

1991vert

10 Year Member
Feb 27, 2004
1,103
7
69
Ludlow, MA
Mar 3, 2004
#3
  • Mar 3, 2004
  • #3
disconnect the negative(-) side of the battery for like 20 mins to reset the computer. should be done usually after every mod
 

Lynkx

Founding Member
Jul 31, 2001
371
0
0
Vancouver Island BC
Mar 4, 2004
#4
  • Mar 4, 2004
  • #4
Fiqured as much, i just didn't understand why it did it AFTER the heatercore was installed.

But on the same token, the mechanic did disconnect the battery.... since my clocks were all reset, so i don't really know if that'll fix it, but ill try tomorrow in the morning.
 

Lynkx

Founding Member
Jul 31, 2001
371
0
0
Vancouver Island BC
Mar 4, 2004
#5
  • Mar 4, 2004
  • #5
Nope, didn't help.. i disconnected it for 30 minutes, and i've driven the car a few hours now total highway time since heatercore was installed...

No idea anymore, sender dead?... and other ideas guys? thanks.
 

jrichker

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Mar 4, 2004
#6
  • Mar 4, 2004
  • #6
Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html
 

Lynkx

Founding Member
Jul 31, 2001
371
0
0
Vancouver Island BC
Mar 5, 2004
#7
  • Mar 5, 2004
  • #7
thanks, either the sender is dead, or if the check oil light is not stored in the computer, then the guy forgot to plug it back in when he was putting the dash back together.
 

NeQX

Founding Member
Sep 30, 2002
904
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0
Infront Of You, NY
Mar 5, 2004
#8
  • Mar 5, 2004
  • #8
Pop that check engine light out, it's annoying specially if you have no cats.
 

Lynkx

Founding Member
Jul 31, 2001
371
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0
Vancouver Island BC
Mar 6, 2004
#9
  • Mar 6, 2004
  • #9
well, i got 2 cats left to cut... ill do that when i get a good pair of headers...

This light is making me paranoid im gonna bitch at the mechanic who did my heatercore, he forgot to reconnect the anttenne also.
 
P

Pop-Pops-Pony

Founding Member
Nov 5, 2001
254
0
0
Sharpsburg, MD.
Mar 6, 2004
#10
  • Mar 6, 2004
  • #10
Check the plug on the Mass Air...Had a loose plug that gave me fits with the check engine light, had to tie-wrap it in...If the mech. was fumbleing around under the hood he might have bumped it...

Re-check the connection on the O2 sensors too....
 

two_stangs

New Member
Jan 3, 2004
61
0
0
AZ
Mar 8, 2004
#11
  • Mar 8, 2004
  • #11
NeQX said:
Pop that check engine light out, it's annoying specially if you have no cats.
Click to expand...

I hate to jump in on the thread with a question...

But how do you remove the check engine light? Would I have to remove the cluster and remove the bulb?

I am running into the same problem. The light will not go away. Even whan I disconnect the battery to clear the codes. Once I start the car up it's on. It doesn't go away at all. No matter what.
 

jrichker

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#12
  • Mar 8, 2004
  • #12
Pull the codes and fix the problem, you car will run better. Some codes cause the computer to switch to limp mode which causes uses fixed values to run the engine. The car's performance will decrease in limp mode and gas mileage will also go down.

Anyone who tells you to ignore the codes is lacking in education on what the computer does and why it does it. Maybe they should stick to working on carb'd cars instead of SEFI cars.

Here's a book that will get you started with how the Ford electronic engine control or "computer" works.

Ford Fuel Injection & Electronic Engine Control 1988-1993 by James Probst :ISBN 0-8376-0301-3.

It's about $20 from Borders.com see http://www.amazon.com/ . Select boo...very good, and I found it to be very helpful.
 

Lynkx

Founding Member
Jul 31, 2001
371
0
0
Vancouver Island BC
Mar 10, 2004
#13
  • Mar 10, 2004
  • #13
two_stangs said:
I hate to jump in on the thread with a question...

But how do you remove the check engine light? Would I have to remove the cluster and remove the bulb?

I am running into the same problem. The light will not go away. Even whan I disconnect the battery to clear the codes. Once I start the car up it's on. It doesn't go away at all. No matter what.
Click to expand...


do the same as these guys are telling you. Find out what is wrong.. your car might not be proforming as it should be.
 

two_stangs

New Member
Jan 3, 2004
61
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AZ
Mar 10, 2004
#14
  • Mar 10, 2004
  • #14
Lynkx said:
do the same as these guys are telling you. Find out what is wrong.. your car might not be proforming as it should be.
Click to expand...

The wiring Harness for the injectors and egr is getting minimum voltage and needs to be checked or replaced. I found that out and thats what pulling the codes and the engine light is going on.

No good.
 

jrichker

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  • Mar 10, 2004
  • #15
two_stangs said:
The wiring Harness for the injectors and egr is getting minimum voltage and needs to be checked or replaced. I found that out and thats what pulling the codes and the engine light is going on.

No good.
Click to expand...

There are two 10 pin connectors at the back of the upper manifold, one of them has all 8 injector connections. Pull them apart and check for damage. Clean the connector pins and sockets with electrical contact cleaner or non-inflammable brake parts cleaner (same stuff as electrical cleaner in a bigger can). Scrape the pins with an exacto knife and use a jeweler's screwdriver to scrape the inside of the pins. One of the pins is the +12 volt supply to the injectors.

Remember that the computer supplies a ground path for the injectors. The power for the injectors comes through the ECC relay located on top of the computer. They have power to them any time the ignition is on. The computer turns on the ground and completes the circuit, making the injectors fire. Pull an injector wire connector off and look for 12 volts on the red wire when the ignition switch is on. No power, then look for problems with the 10 pin connecter (salt & pepper shakers at the rear of the upper manifold)
 

4dStang

Banned
Oct 23, 2002
718
0
0
Near St Louis, Missouri
Mar 10, 2004
#16
  • Mar 10, 2004
  • #16
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!


I did it and have had no worries yet. I have three major systems I watch: Temp, Charge and Oil pressure. If you got them screw everything else!!!!!!!!



To pull the bulb, Take out the cluster, unscrew the bulb, replace the cluster! Simple..
 

Lynkx

Founding Member
Jul 31, 2001
371
0
0
Vancouver Island BC
Mar 11, 2004
#17
  • Mar 11, 2004
  • #17
Nah dude, thats a redneck answer and you should be ashamed!

Besdies, im not one to run away from a challenge or cheat.

this beast, its getting fixed. However, took it to the mechanic who did the job, he didn't pull any wires, just balanced the dash just enough so he didn't have to.. the only thing we could think of was the sender unit, and its fine.

Last resort until i fiqure out some idea's is a simple oil change, maybe the filter is blocked? car is running just fine, been driving it for a week, no problems.
 

jrichker

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Mar 11, 2004
#18
  • Mar 11, 2004
  • #18
4dStang said:
PULL THE LIGHT BULB OUT!!!!
PULL THE LIGHT BULB OUT!!!!

I did it and have had no worries yet. I have three major systems I watch: Temp, Charge and Oil pressure. If you got them screw everything else!!!!!!!!

To pull the bulb, Take out the cluster, unscrew the bulb, replace the cluster! Simple..
Click to expand...

Try as we may, you just can't educate some people...

I guess he doesn't understand the concept of Limp mode and the reduced performace it brings.
 
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