Running RICH......I need to resolve this,,, i'm stumped
08-31-2004, 08:05 PM
#1
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Running RICH......I need to resolve this,,, i'm stumped Here we go
I have been trying to figure this one out for a long time and I am comming up short.
I have installed a LS1/4L60E in a Jeep wrangler
I have a custom 2.5" to a single 3" Y pipe, catco cat, magnaflow exhaust, everything else is in stock form. fuel pressuer is at 58psi
I know i'm running rich because my tail pipe is coated in black soot within a day and a half, the smell comming from my tailpipe burns my eyes and i am getting 14 to 15 mpg when others with the same setup (including wheel size and gear ratio) is getting 20 to 23 mpg. I have no error codes thrown and it does say that my o2 sensors are working
I do have auto tap but I don't know what to look for as far as good, normal readings and I just dont know exactally what is involved that would make the motor run rich.
The Question: In autotap what do i look for and what is the reading it should be at, for normal driving and some wot, that would make my motor run rich.
pleeeeeeeeeeeeeease help me.
Steve S
Michigan
I have been trying to figure this one out for a long time and I am comming up short.
I have installed a LS1/4L60E in a Jeep wrangler
I have a custom 2.5" to a single 3" Y pipe, catco cat, magnaflow exhaust, everything else is in stock form. fuel pressuer is at 58psi
I know i'm running rich because my tail pipe is coated in black soot within a day and a half, the smell comming from my tailpipe burns my eyes and i am getting 14 to 15 mpg when others with the same setup (including wheel size and gear ratio) is getting 20 to 23 mpg. I have no error codes thrown and it does say that my o2 sensors are working
I do have auto tap but I don't know what to look for as far as good, normal readings and I just dont know exactally what is involved that would make the motor run rich.
The Question: In autotap what do i look for and what is the reading it should be at, for normal driving and some wot, that would make my motor run rich.
pleeeeeeeeeeeeeease help me.
Steve S
Michigan
08-31-2004, 08:46 PM
#2
o2s could be bad, reporting the wrong af to the computer, or, it could be a programming problem, it may be sticking in cell 22, and so you are always in power enrichment mode. also, what regulator are you using for the fuel system? is it a flat 58 lbs across the rpm range ? or is if vacuum referenced? if it gets higher pressure as the motor speed increases then that is your problem, you need to change the programming in your car. or it could be your mass air meter is taking a dump, or it really dirty... you could try unpluging it, and start the jeep, try to keep it running till it takes over in speed density mode, then just see if it still runs rich. jes,
email me if you need some help with anything,
email me if you need some help with anything,
08-31-2004, 09:14 PM
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I have a Mallory adjustable regulator and it does have a vacuum referance but I have a tube connected to it and it is just vented.
The MAF sensor looks clean
Some people say bad plugs or wires as well but the motor has 22,000 miles on it when I installed it and I need a little more convencing on that one.
What could it be
The MAF sensor looks clean
Some people say bad plugs or wires as well but the motor has 22,000 miles on it when I installed it and I need a little more convencing on that one.
What could it be
08-31-2004, 10:01 PM
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Originally Posted by wait4me
you could always check the plug wires.. just do an ohm resistance check on them. they should all be the same, ive seen alot of bad plug wires lately for some reason, alot being aftermarket... jes
09-01-2004, 05:15 PM
#7
Log your o2 voltages and your ltrims. The ltrims should ideally be slightly negative, around -5 to zero. If they are way off one end of the scale or the other, that will tell you something. If the o2 voltages are not varying, but staying high, that will tell you something too.
How old are the o2 sensors? They can drift off without setting codes yet.
If you have an exhaust leak upstream of the sensor, or downstream within a few inches of the sensor, it will see the extra oxygen and think you're running lean and dump in more fuel.
How old are the o2 sensors? They can drift off without setting codes yet.
If you have an exhaust leak upstream of the sensor, or downstream within a few inches of the sensor, it will see the extra oxygen and think you're running lean and dump in more fuel.
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09-01-2004, 05:52 PM
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Originally Posted by John_D.
Log your o2 voltages and your ltrims. The ltrims should ideally be slightly negative, around -5 to zero. If they are way off one end of the scale or the other, that will tell you something. If the o2 voltages are not varying, but staying high, that will tell you something too.
How old are the o2 sensors? They can drift off without setting codes yet.
If you have an exhaust leak upstream of the sensor, or downstream within a few inches of the sensor, it will see the extra oxygen and think you're running lean and dump in more fuel.
How old are the o2 sensors? They can drift off without setting codes yet.
If you have an exhaust leak upstream of the sensor, or downstream within a few inches of the sensor, it will see the extra oxygen and think you're running lean and dump in more fuel.
I know that I do not have an exhaust leak and the exhaust is all new, I did check around the exhaust manafolds as well.
The o2 sensors are the origional ones, they have about 23,000 miles on them
When you talk about the ltrims, is that at idel?
09-01-2004, 06:44 PM
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Originally Posted by Flyman
Thanks John for your reply
I know that I do not have an exhaust leak and the exhaust is all new, I did check around the exhaust manafolds as well.
The o2 sensors are the origional ones, they have about 23,000 miles on them
When you talk about the ltrims, is that at idel?
I know that I do not have an exhaust leak and the exhaust is all new, I did check around the exhaust manafolds as well.
The o2 sensors are the origional ones, they have about 23,000 miles on them
When you talk about the ltrims, is that at idel?
09-02-2004, 09:00 PM
#11
Originally Posted by Flyman
When you talk about the ltrims, is that at idle?
If you log tps, mph, ltrims, fuel cell, you can see where you have different ltrims for different conditions.
For the most part, if the ltrims and o2 voltages look right, and it's still noticeably rich, then something isn't right with the feedback loop...
Maybe the pcm is staying in open loop. There may be a parameter you can log for this. Maybe the coolant temp is staying cold enough for this to happen, or the pcm thinks the coolant is cold. If so, the pcm will be adding fuel (as if the choke was closed on a cold carb motor).
Possibly it's running in some default mode because some sensor is dead.
One last thought, a misfire will make the o2 sensors think the engine is running lean. Because the sensor sees oxygen. The misfiring cylinder is dumping fuel and oxygen out the exhaust but the sensor only sees the oxygen, and dumps in even more fuel.
