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Running rich, real rich

  • Thread starter Thread starter Andres2882
  • Start date Start date Aug 15, 2005
A

Andres2882

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Jan 29, 2004
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Aug 15, 2005
#1
  • Aug 15, 2005
  • #1
Ahh the smell of gasoline wafting through the air. Honestly though, I'm living a nightmare, a 5mpg nightmare. It all started when I got my car back from the SFC install. After about 5-6 miles or when my temperature sensor reaches about 180 degrees, it seems, my car starts running like total garbage. I'm tripping codes 41, 91, 96 from the CM, which is odd, because my car is running very very rich. There is literally black droplets coming out of my tailpipes. I tested both of my O2 sensors and they are reporting .9V, in other words, super rich. So can anyone tell me what the deal is?

Yount? HISSIN? Joe? Rick?

Anyone?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
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Aug 15, 2005
#2
  • Aug 15, 2005
  • #2
Did the guy who welded the SFC on disconnect the battery when he welded them up??

It's possible he fried the EEC
 

CRASH7772

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Apr 27, 2003
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NH
Aug 15, 2005
#3
  • Aug 15, 2005
  • #3
Have you checked TPS voltage, dirty Mass Air sensor, EGR, FPR?
 

NKau

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Aug 15, 2005
#4
  • Aug 15, 2005
  • #4
What Mike is saying is to call up one of your buddies with an '89-'93 5-speed car, pull out the computer, put it in your car and see what happens.
 
A

Andres2882

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#5
  • Aug 15, 2005
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I really think I may cry.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Aug 15, 2005
#6
  • Aug 15, 2005
  • #6
First thing I would do is haul back down to the shop (sooner is better) and see what they say. I would play it cool with them and see what they volunteer.

Worst case, a new puter is 100 bucks-ish. Swapping it with a buddy's would be cool. J/Y puters are cheaper, but that adds a new variable (does it work itself - unknown history).

IIRC I read that the puter can handle a double-voltage reverse-polarity hookup and survive. How that relates to welding I dont know. Mike, could the welding take out just the O2's (given the proximity and their sensative nature)?

I am sure Mike, Tom and the other wizards you mentioned can take care of you.

Good luck!
 
A

Andres2882

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#7
  • Aug 15, 2005
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You think its safe to take it back to the same speed shop? It seems almost certain that they f'd something up in the first place.
 

NKau

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#8
  • Aug 15, 2005
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People make mistakes. If the manager/owner is decent, he should take care of whatever problems they caused. Like HISSIN50 said, I'd contact them as soon as possible and see what you can work out.

Sounds like you've been having a lot of bad luck lately.........ever get that intake taken care of?
 
A

Andres2882

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Aug 16, 2005
#9
  • Aug 16, 2005
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/sigh

Not yet Nick. Maybe this is just God's way of saying to buy a whole new longblock? Sounds like that's the message I'm getting, chuckle! Oh well.
 

Rick 91GT

Mustang Master
Nov 29, 1999
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Aug 16, 2005
#10
  • Aug 16, 2005
  • #10
Mustang5L5 said:
Did the guy who welded the SFC on disconnect the battery when he welded them up??

It's possible he fried the EEC
Click to expand...

I am leaning towards this as well.....but it seems odd that is still runs at all, usually they just go from what I have seen.
 
A

Andres2882

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Aug 16, 2005
#11
  • Aug 16, 2005
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Well, as it usually happens, my drive to the mechanic was picture perfect. Speed shop called back to ask me the symptoms because they said their test drive was also event free. I told them to let her run for a bit and then the problems will come out. They haven't called back so I assume something negative happened. Why would the car need to warm up/ be driven a certain distance for problems to unfold?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Aug 16, 2005
#12
  • Aug 16, 2005
  • #12
Rick 91GT said:
I am leaning towards this as well.....but it seems odd that is still runs at all, usually they just go from what I have seen.
Click to expand...

Yeah, i've seen comps go out totally and some run but poorly.

I just speculated that since he just had something welded on the car and now it runs like crap, that my money would be on a fried EEC.

It could be something else like unplugged o2's or something stupid like that, but i cannot look at the car unfortunately to give a better guess.
 
A

Andres2882

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Aug 17, 2005
#13
  • Aug 17, 2005
  • #13
So the speed shop calls and tells me that they cannot find anything out of the ordinary. They say they drove it all around town and the head guy even took it with him on a lunch run to see if they could get a check engine light or something to pop. According to them, absolutely no issues. Is it possible the EEC finally sorted itself out? I'm hoping they figured they fried something and then replaced it so save face. Well I'll report back on how its running tomorrow when I pick her up.
 

TenorPlayinGuy

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Aug 3, 2001
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Aug 17, 2005
#14
  • Aug 17, 2005
  • #14
sometimes you just need to pull the battery and let the darn thing reset it self. Just like Windows. It may crash but just hit the reset and your good to go for a while longer
 
A

Andres2882

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Aug 18, 2005
#15
  • Aug 18, 2005
  • #15
Picked up the car, absolutely no problems. They said they did absolutely nothing, just never ran bad for them. I don't know if I believe that, they called to ask why my upper intake was missing a bolt so they had to be looking awful close at something to notice that. Anyway, cheers for them if they did something and if they didnt, cheers for whatever or whomever. My car works again, I'm a happy man.
 
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