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Running rich, where to start?

  • Thread starter Thread starter Gixxer750
  • Start date Start date Jun 29, 2004
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Gixxer750

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Saint John NB, Canada
Jun 29, 2004
#1
  • Jun 29, 2004
  • #1
Well this year I have been having some issues with running rich at idle and at running speeds, where should I start first?? Should I replace both O2's and see if that helps, or is there something else I can check.


Current Set up is an 87 GT with smog delete Headers, O/R H dumps, etc. MAF conversion, and basic bolt on's. Cobra Upper and lower, and a few other things, timing is set at 10 degrees.

Should I go wide ban O2 and see how that works??
 

ECU5.0

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Jan 10, 2004
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Jun 29, 2004
#2
  • Jun 29, 2004
  • #2
how do you know you are running rich?
 

Gixxer750

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Saint John NB, Canada
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#3
  • Jun 29, 2004
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ECU5.0 said:
how do you know you are running rich?
Click to expand...

Can smell it. So can people behind me.
 

ECU5.0

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#4
  • Jun 29, 2004
  • #4
well youre not running any cats and now smog pump so thats kind of normal that they will smell your car. everytime i drive my car i get out smelling like i just cut the grass. maybe try gettin an adjustable fuel pressure regulator and adjusting your fuel pressure. o2 sensors might help too
 

Gixxer750

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#5
  • Jun 29, 2004
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Well I know 3 other guys around me runnign the same way and they don;t have half the smell of gas that I do. MAybe I will swap out their O2's and see how that works for me

How bout timing?? Will that help if I advance it??
 

cardudeusa

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Oct 22, 2002
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Jun 29, 2004
#6
  • Jun 29, 2004
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I've had that same problem ever sence I put on the L/T's got rid of the cats and added dumps, are you sure its not just exhaust fumes?
 

ECU5.0

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#7
  • Jun 29, 2004
  • #7
Gixxer750 said:
Well I know 3 other guys around me runnign the same way and they don;t have half the smell of gas that I do. MAybe I will swap out their O2's and see how that works for me

How bout timing?? Will that help if I advance it??
Click to expand...

yeah, advancing the timing might help because it will ingite the fuel sooner and give it longer to burn. but i would also invest in an AFPR and gauge
 

Gixxer750

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cardudeusa said:
I've had that same problem ever sence I put on the L/T's got rid of the cats and added dumps, are you sure its not just exhaust fumes?
Click to expand...


Well today after getting hard on it, the guy pulled up beside me at the lights waving his hands and saying my car smelt like pure un burnt gas

I would just like to try to calm down the smell a bit, I personally think it is a bit excessive for the gas smell.
 

willys1

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Dec 2, 2003
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Jun 29, 2004
#9
  • Jun 29, 2004
  • #9
Are the tips of your tailpipes black??
 

Gixxer750

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Saint John NB, Canada
Jun 29, 2004
#10
  • Jun 29, 2004
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willys1 said:
Are the tips of your tailpipes black??
Click to expand...


Running dumps I will have to crawl under and check tomorrow.
 

willys1

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#11
  • Jun 29, 2004
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Thats what I would do.Change the 02 sensors,and go from there.Definitly check your turndowns for blackness!
 
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89rdgt

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Apr 24, 2004
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Jun 29, 2004
#12
  • Jun 29, 2004
  • #12
pull a plug check out what it looks like. is it black?? is black smoking coming out the tail pipe? whats your mpg like? all those are great indicators of running rich especially pulling the plug and looking at it. good luck
 

Gixxer750

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#13
  • Jun 29, 2004
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89rdgt said:
pull a plug check out what it looks like. is it black?? is black smoking coming out the tail pipe? whats your mpg like? all those are great indicators of running rich especially pulling the plug and looking at it. good luck
Click to expand...


Well when I changed my plugs last month I had at least 4 of them that were black. My gas milage in my opinion sucks. $30 gets me about 220 KMs max. that is all city driving. I will pop out my O2's bump my timing up to 14* or so and pick up an AFPR and see how that helps. Any other ideas??
 

willys1

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Dec 2, 2003
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Jun 29, 2004
#14
  • Jun 29, 2004
  • #14
Gixxer750 said:
Well when I changed my plugs last month I had at least 4 of them that were black. My gas milage in my opinion sucks. $30 gets me about 220 KMs max. that is all city driving. I will pop out my O2's bump my timing up to 14* or so and pick up an AFPR and see how that helps. Any other ideas??
Click to expand...
Whats kind of gears do you have?220 miles from a tank of gas in city driving doesnt sound to abnormal.
 

Gixxer750

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Jun 29, 2004
#15
  • Jun 29, 2004
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willys1 said:
Whats kind of gears do you have?220 miles from a tank of gas in city driving doesnt sound to abnormal.
Click to expand...

Stock Gears. And that is Kilometers not Miles. So
220kms / 1.66 = 132.5 miles per $30 of fuel.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jun 29, 2004
#16
  • Jun 29, 2004
  • #16
willys1 said:
Whats kind of gears do you have?220 miles from a tank of gas in city driving doesnt sound to abnormal.
Click to expand...
he is in Canada - i think he said 220 clicks.
 

willys1

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#17
  • Jun 29, 2004
  • #17
HISSIN50 said:
he is in Canada - i think he said 220 clicks.
Click to expand...
oops,yeah your rite.How many miles is that??
 

cardudeusa

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Jun 29, 2004
#18
  • Jun 29, 2004
  • #18
willys1 said:
oops,yeah your rite.How many miles is that??
Click to expand...

Gixxer750 said:
Stock Gears. And that is Kilometers not Miles. So
220kms / 1.66 = 132.5 miles per $30 of fuel.
Click to expand...



Yeah, that is pretty crappy mileage!! I can get atleast 250-290 miles to a tank, depending on driving conditions.
 

5ive.oh

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Feb 23, 2001
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Rocky Mountain House, AB
Jun 29, 2004
#19
  • Jun 29, 2004
  • #19
I am in the same boat, black exhaust tips, stinking when I get on it. I've only had the car for two weeks so I am just getting to know it.
 
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89rdgt

New Member
Apr 24, 2004
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Jun 29, 2004
#20
  • Jun 29, 2004
  • #20
Gixxer750 said:
Stock Gears. And that is Kilometers not Miles. So
220kms / 1.66 = 132.5 miles per $30 of fuel.
Click to expand...


whooa that is pretty crapy if you ask me. if you have a multimeter on accesses you can tap into the signal return line on your o2 sensor in closed loop it should bounce between 0-1v faily quick. (note higher voltage is richer mixture lower voltage is leaner.) if your running rich itll show with a higher voltage. If it is switching pretty slow then it is probably starting to get lazy and you need a new one. Also check your maf. I assume your running an aftermarket intake if you use the oils to clean your filter and you heavily oil it then it can contaminate your maf and will make you run rich. Check the little heater inside your maf to see if it is black or dirty looking. good luck
 
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