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At my wits end; $60 MIL Elem.'s still do not work after trying everything to fix it

  • Thread starter Thread starter Craig Mack
  • Start date Start date Jan 5, 2004

Craig Mack

Busted Buffing the Bishop
Founding Member
Mar 9, 2002
801
0
0
Lake Mary, FL
Jan 5, 2004
#1
  • Jan 5, 2004
  • #1
Ok, so when I bought my UPR offroad x-pipe from UPR a few weeks ago, I went ahead with the $60 plug in mil eliminators too.

1st try: This was during the install of the x-pipe itself. The battery was unplugged before even starting the install. MIL eliminators were plugged in between the two rear sensors, zip tied out of harms way, battery plugged back in, and car started. Light comes on about 30 miles down the road.

2nd try: MIL plugs were switched in fear that I accidentally installed them on the wrong sides. Car was started, light goes away, but comes back about 30 miles down the road.

3rd try: So I go down to my local tranny shop, becuase they have a diagnostic tool to tap into the ECU and scan it for problems. The only problem it read was "rear o2 sensor malfunction". So, we reset it and cleared the codes. Problem solved right? Well, for about the first 30 miles, then the CEL came on again.


So i've been driving for about two weeks with my check engine light on. It is an eyesore but I can live with that part. I'm worried now that when I have a real engine problem, I'm not going to be able to tell. I'm also a little concerned that my car will be running differently now. I heard that the rear o2 sensors don't effect anything, so the car doesn't run leaner or richer, but I still wonder if i'm losing any power.

The main part is, I spend $60 on two plug ins that don't work. I had the tranny shop inspect my o2 sensors when they were rebuilding my tranny, and they said they were fine. So I have tried everything within my power, and don't know what to do now. I need your guys advice.

Thanks in advanced...
 
S

Snakeswinger

New Member
Sep 13, 2002
39
0
0
Beltsville MD
Jan 5, 2004
#2
  • Jan 5, 2004
  • #2
Could be faulty mil eliminator, get someone with a good graphing scanner so you can see what actually is going on with the rear O2's. Also a chip or a predator can set the computer to totally ignore those sensors
 

Craig Mack

Busted Buffing the Bishop
Founding Member
Mar 9, 2002
801
0
0
Lake Mary, FL
Jan 6, 2004
#3
  • Jan 6, 2004
  • #3
Snakeswinger said:
Could be faulty mil eliminator, get someone with a good graphing scanner so you can see what actually is going on with the rear O2's. Also a chip or a predator can set the computer to totally ignore those sensors
Click to expand...

Who would have a graphing scanner? I don't know what that is...

Ya, I may look into getting a chip soon, although I don't know if I want to dish out all the $$ for a chip if I won't feel the HP/TQ.
 

COBRA90GT

Mustang Master
Sep 22, 2001
6,654
0
87
HOCKEYTOWN ® , MI
Jan 6, 2004
#4
  • Jan 6, 2004
  • #4
Sounds like you need a new rear O2 sensor(s)...remember, MIL Elims need a properly functioning O2 sensor in order for them to work correctly.
 

budguy1967

New Member
Sep 18, 2002
43
0
0
Wichita, Kansas
Jan 6, 2004
#5
  • Jan 6, 2004
  • #5
I agree, faulty 02 sensor.
 

Craig Mack

Busted Buffing the Bishop
Founding Member
Mar 9, 2002
801
0
0
Lake Mary, FL
Jan 6, 2004
#6
  • Jan 6, 2004
  • #6
budguy1967 said:
I agree, faulty 02 sensor.
Click to expand...

Well, they were fine before I did the install, what would make them foul as soon as I install the MIL eliminators?
 

Tat98Cobra

Founding Member
Nov 2, 2002
681
0
0
Jan 6, 2004
#7
  • Jan 6, 2004
  • #7
Craig Mack said:
Well, they were fine before I did the install, what would make them foul as soon as I install the MIL eliminators?
Click to expand...

Remember also - that mil eliminators (if they're working properly!) only take care of a rear-02 , cataylist related CEL. They wont account for any other sensor issues. My point - is it possible you're getting the CEL from something else besides the rear 02's? GEt it scanned, and post the code

peace
 

5.0's 4 ever

The #1 Stunna
Founding Member
Jan 22, 2000
5,794
0
76
Orlando, FL
Jan 6, 2004
#8
  • Jan 6, 2004
  • #8
I would personally like to have a real ford diagnostic tool hooked up to the car to pull codes. But to me it sounds like the mil eliminators are not doing their job with the cat monitor sensors. Where did you buy these mil eliminators from? I bought mine from CFM and had zero problems from them while I ran them on my car. My friend now runs them on his 98 cobra and they are working properly on his car also.
 
T

tranzlucent662

New Member
Apr 23, 2003
126
0
0
Jan 6, 2004
#9
  • Jan 6, 2004
  • #9
I had the same problem with my plug in MIL's. I finally said f it and went with the splice in MIL's from PEP. No problem since then.
 

sinisterblack98

Sometimes I just lay on my garage floor and look u
Founding Member
Apr 11, 2000
967
0
0
Motor City, MI
Jan 6, 2004
#10
  • Jan 6, 2004
  • #10
If they're the ones made by Casper they have issues working with '97 and '98 computers. I had the chip re-flashed to eliminate the rear O2 monitors, after trying two different pairs on my '98.
 
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