What the F*ck is wrong with my car? Im fed up
10-06-2008, 04:19 PM
#1
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What the F*ck is wrong with my car? Im fed up My SES light came on a few weeks ago, bank 1 and 2 o2's were bad.
I replaced them with 'universal' do-it-yourself o2's 'cause they were cheaper and the light came back on again after 150 miles.
I then replaced them one more time with the actual plug in o2's yesterday.
I also replaced the plug wires, fuel filter and changed back to my oem MAF.
******* light is on again for the same thing.
Mods are: pacesetter lt's, ory, x-pipe.
Car has been tuned and the rear o2's were deleted.
Why does this keep happening? This is beyond me and I need help.
Ive gotta get the car inspected this month.
I replaced them with 'universal' do-it-yourself o2's 'cause they were cheaper and the light came back on again after 150 miles.
I then replaced them one more time with the actual plug in o2's yesterday.
I also replaced the plug wires, fuel filter and changed back to my oem MAF.
******* light is on again for the same thing.
Mods are: pacesetter lt's, ory, x-pipe.
Car has been tuned and the rear o2's were deleted.
Why does this keep happening? This is beyond me and I need help.
Ive gotta get the car inspected this month.
10-06-2008, 05:24 PM
#4
https://ls1tech.com/forums/general-maintenance-repairs/995852-need-explanation-ses-code.html
Your O2 sensors are telling you the engine is running lean. Don't shoot the messenger!
Your O2 sensors are telling you the engine is running lean. Don't shoot the messenger!
10-06-2008, 07:34 PM
#7
Who did your tune? If it is a crappy tune and their A/F isn't on then that would explain alot. That or fuel delivery problem and fuel pressure is low is a possibility also. Check fuel pressure at the rails and see if it is still what it's supposed to be... When was the last time you changed fuel filters too. Know that seems outlandish, but if you've got mileage and have the stock filter.
Mike
Mike
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10-06-2008, 07:41 PM
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I've had this same tune for over a year with no changes made to the car.
In my original post I said ive already changed the fuel filter.
But I have not checked fuel pressure. What should it read at?
In my original post I said ive already changed the fuel filter.
But I have not checked fuel pressure. What should it read at?
10-06-2008, 07:44 PM
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been down this road bought to many sensors. Go buy rear O2 sensors from like a 2002 corvette and and toss the extensions now on the vette o2 sensors pry the veins open taking care not to touch the inside filament thats white just take your time you will be fine. i found that opening it helps get more exhaust in there. do one side at a time to make sure thats what it is.
, I havent heard any major ones with the engine running though..... 
10-06-2008, 08:14 PM
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There's two ways to get lean codes. One is real
lean delivery (pump, filter, MAF) and the other is
bogus O2 sensor readings, like tends to happen
with uncoated headers when the weather turns
cool. O2 sensor codes may be telling you about
that, lean codes would come later when it has
tried and failed to trim back in (perhaps based
on bullshit data from the sensors, but still).
Without the tools you are in for a tougher time
troubleshooting. So start with basic hygeine and
see what that gets you. Might clean the old MAF
just so you can say you did.
If you have a good DMM you can get a look at
O2 voltage, at least as an average. Here's a way
to tell if it's a real mixture problem or a heat
problem. Do a PCM reset first to lose all the old
fuel trims. Foot-idle the thing at about 3000RPM
for a minute and watch the DMM voltage as you
let it back out to idle. Should see about 500mV
but a lot of "flickering", voltage moving around
at the higher RPM. When you drop to idle, you
should see it "flicker" more slowly about the same
center point. If it starts out this way but then
starts to swing wider and slower, and then just
goes to about zero, you have a sensor that is
just not kept hot enough. That's an exhaust
problem - losing too much heat.
If you don't even have a DMM (which go for a
big $5 at Harbor Freight) then you may as well
sacrifice a chicken. The PCM demons despise
helplessness and torment all those they can.
lean delivery (pump, filter, MAF) and the other is
bogus O2 sensor readings, like tends to happen
with uncoated headers when the weather turns
cool. O2 sensor codes may be telling you about
that, lean codes would come later when it has
tried and failed to trim back in (perhaps based
on bullshit data from the sensors, but still).
Without the tools you are in for a tougher time
troubleshooting. So start with basic hygeine and
see what that gets you. Might clean the old MAF
just so you can say you did.
If you have a good DMM you can get a look at
O2 voltage, at least as an average. Here's a way
to tell if it's a real mixture problem or a heat
problem. Do a PCM reset first to lose all the old
fuel trims. Foot-idle the thing at about 3000RPM
for a minute and watch the DMM voltage as you
let it back out to idle. Should see about 500mV
but a lot of "flickering", voltage moving around
at the higher RPM. When you drop to idle, you
should see it "flicker" more slowly about the same
center point. If it starts out this way but then
starts to swing wider and slower, and then just
goes to about zero, you have a sensor that is
just not kept hot enough. That's an exhaust
problem - losing too much heat.
If you don't even have a DMM (which go for a
big $5 at Harbor Freight) then you may as well
sacrifice a chicken. The PCM demons despise
helplessness and torment all those they can.
10-06-2008, 08:27 PM
#17
As far as vacuum leaks go, start by checking the PCV line, they are known to crack. Spray carb cleaner around any and all vacuum lines/sources, listening for a change in idle speed. Brake booster line (and even the booster itself), intake manifold gasket, fuel pressure regulator, anywhere there is vacuum.
10-06-2008, 08:43 PM
#19
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alright thanks formula i sure will-
and jimmy, its kinda funny because this probs started happenin when the weather was startin to get cool. My headers are coated but that **** is flaking off cause they're over two years old. haha
and jimmy, its kinda funny because this probs started happenin when the weather was startin to get cool. My headers are coated but that **** is flaking off cause they're over two years old. haha
