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Discussion Starter #1
So as you may know i just finished the pi swap and my car is running lean. apparently it was running lean before the swap. I had some codes read today that showed the following:

P1131-Lack of Upstream Heated Oxygen Sensor/Sensor Indicates Lean/Bank1
P1132-Lack of Upstream Heated Oxygen Sensor/Sensor Indicates Rich/Bank1
P1151-Lack of Upstream Heated Oxygen Sensor/Sensor Indicates Lean/Bank2
and one random o2 code for the downstream. but i have eliminators and the downstream has no effect on the air fuel ratio.

My symptoms are:
after the car gets warm the idle surges. 200rpm-600rpm
when driving at a constant speed and press the clutch in, as the rpms fall it dies. and my air fuel ratio gauge is reading lean constantly.

I replaced oxygen sensor bank 1 upstream today and it had no effect on the issue. I will try to replace bank 2 as well tomorrow and test the injectors. I have no clue what is going on. any ideas? :confused:
 

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Rollin' 18/ pushin' 2
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8,333 Posts
The surging and eratic idle seems like an Idle Air Control valve. That's how mine acted when it went out. But I got an IAC code. I didn't get the 02 sensor codes your getting.

I'd start by double checking all your work.
 

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Discussion Starter #3
i am assuming its just the fact that i have alot of bolt ons and the pi heads, cams, and intake all with no tune. i changed out the bank 1 o2 sensor and got rid of codes 1131 and 1132, now i have 1151 pending its basically saying the car is compensating for an over-rich condition. This is because i have the vacuum unplugged from my fuel pressure regulator so my fuel will be at 42 insead of 30. im getting it tuned this weekend so we will see what happens
 
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