P1152
Lack Of Upstream HO2S Switch, Sensor Indicates Rich, Bank No. 2


P1132
Lack Of Upstream HO2S Switch, Sensor Indicates Rich, Bank No. 1

DTCs
P1132 - Lack of Switching - Sensor Indicates Rich, Bank 1

P1152 - Lack of Switching - Sensor Indicates Rich, Bank 2

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These are my 2 codes I have on my truck.
A bout a month ago I replaced BOTH FRONT O2 sensors.

Are the front O2 sensors he "upstream Ho2s Switch"?

Could this be caused by a Bad MAF?
Could this be cuased by bad REAR O2 sensors? (I didn't replace the rear ones, on the front)


HELP.
(at least it is running rich and not LEAN)



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I've done a little search and this is what I came up with, Can someone help me narrow it down a little

P1130 - Lack of HO2S-11 Switch, Fuel Trim at Limit The HEGO Sensor is monitored for switching. The test fails when the HO2S fails to switch due to circuit or fuel at or exceeding a calibrated limit. Electrical:
Short to VPWR in harness or HO2S
Water in harness connector
Open/Shorted HO2S circuit
Corrosion or poor mating terminals and wiring
Damaged HO2S
Damaged PCM
Fuel System:
Excessive fuel pressure
Leaking/contaminated fuel injectors
Leaking fuel pressure regulator
Low fuel pressure or running out of fuel
Vapor recovery system
Induction System:
Air leaks after the MAF
Vacuum Leaks
PCV system
Improperly seated engine oil dipstick
EGR System:
Leaking gasket
Stuck EGR valve
Leaking diaphragm or EVR
Base Engine:
Oil overfill
Cam timing
Cylinder compression
Exhaust leaks before or near the HO2S(s)
A fuel control HO2S PID switching across 0.45 volt from 0.2 to 0.9 volt indicates a normal switching HO2S.
P1131 - Lack of HO2S-11 Switch, Sensor Indicates Lean A HEGO sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time. See Possible Causes for DTC P1130

P1132 - Lack of HO2S-11 Switch, Sensor Indicates Rich A HEGO sensor indicating rich at the end of a test is trying to correct for an over-lean condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time. See Possible Causes for DTC P1130


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P1152 - Lack of HO2S-21 Switch, Sensor Indicates Rich A HEGO sensor indicating rich at the end of a test is trying to correct for an over-lean condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time. See Possible Causes for DTC P1130

 

Did you recently remove the intake boot? Check to be sure it is secured on the bottom of the throttle body as well and the two PVC hoses on the bottom. Those codes come with to much intake air normally.

 

Mark, I don't know if it was the air this past weekend but my truck threw codes also right & left bank too rich and a PO107 code for MAP sensor re booted the system and that helped for a half a day but they came back had auto zone read and clear havent came back since yesterday evening. I beat on it last night and on the way to work to try to make them come back but no luck (Thats a Good Thing Right?)


Suavy

 

Actually Mark, what that means is your truck did exhibit a lean condition. The PCM saw this and compensated by dumping more fuel. This caused a rich condition which the O2 sensor saw. These are the same codes I had on my truck in the spring.

That's how it was explained to me by my cousin who's a powertrain engineer in Dearborn. Of course, my issue was the O2 extension. Since you don't have headers, that's not the cause.

I really don't know what it could be, but it's not the rear 02's. Those just make sure the cats are doing their job. Since you had the problem on both banks (both sides), I would agree with 1BadTk. Look for ways air could be getting in.

 

that doesn't make any sense. if the pcm saw a lean condition to begin with, then why wouldn't it have stored lean codes? and if it did try to add fuel to compensate for a lean condition, then why once the air/fuel ratio returned to an acceptable range did the pcm CONTINUE to add fuel???

IF I'm understanding what the thead starter is saying then, IMHO, not to be a wisea$$ but you need to call your cousin and ask him to explain it again.

if the truck went lean, you would have lean codes, not rich codes.

the pcm should not add enough fuel to cause rich codes, only enough to get things back to normal or near zero on the short and long fuel trims.

just my .02

although it's not quite as simple as that because there is more than one fuel table, and there are alot more to the fuel tables than just the hegos. there are various other inputs and rpms and loads to consider.

those codes indicate that the sensors are not switching, either both sensors went bad and are stuck on rich voltage, or the truck is running so rich that the pcm can't compensate by taking fuel away.

BTW, do you have any adaptive fuel strategy limit reached codes?

good luck.

later,
chris

 

adaptive fuel what ?

I have a chip from SCT and a PCM reflash.

Could that handle it?
I replaced BOTH front O2 sensors about a month ago.

There were no loose connections or disconnects from the vacuum system

 

Most of the time your truck throws a rich code it mean its running lean and the computer is adding fuel to richen it up and vise versa. This is usually the case in adding a pulley, cold air, exhuast, ect... with out adding a chip. Also bad tunes and a few other things usually result of vaccum leaks or other malfunctions such as 02 sensors. So there is really quite a bit of options and things to check. SCT can fix it for you if its not a mechanical problem to begin with.


JimIIi

 

Chris, I wondered the same thing myself, why it wouldn't store a lean condition code first, then a rich condition. As for what my cousin told me, I'm going from memory from our conversations a few months ago, so I"m probably all wrong. Also, while he's part of power train, I don't think engine calibration is his area of expertise and he even told me that.

I can confirm that for my problem it was a o2 sensor that wasn't reading at all. It was stuck at a certain voltage. That jives with the official explanations Mark posted.

 

Chainsaw, I just looked up the code description.

here it is to add to the confusion:
I have no idea what "at the end of a test" means.

but I still COMPLETELY disagree with this line of thinking:

I don't think a truck will throw a rich code because it's running lean.

by way of trying to give an example to support my point of view... try this if you'd like.

go outside and start your truck. let it idle. now unplug a vacuum line from the side of your intake manifold, midplate, brake booster, etc. you have created a vacuum leak and thereby created a lean condition correct?. now drive it or let it run until the check engine light comes on. based on the above line of thinking the truck will have set a rich code??? I don't think so.

but as always, it's possible that I'm mistaken as well, i'm only human like everybody here.

i'd like to hear more discussion.

later,
chris

 

From my source;

vacumm leak= computer adds fuel and sets a lean code once it is out of fuel control for extended periods. It knows its adding too much fuel because of a lean condition

Rich code= the computer is taking away so much fuel that it knows the engine is running rich and it needs less and less fuel. those are negative fuel trims that are out of range for extended periods of time.(this would happen with a popped fuel regulator diaphram, and fuel being sucked into intake via the vacumm line)

The only time that these dont apply is when you have a misfire and the 02's see all that extra oxygen and add fuel, when it is not needed.

and lean does not equal melted cats

Later...

Bruce

 

Whoa...

OK, so does anyone have any suggestions as to what I should do?

 

Sell you truck to some unsuspecting rube and buy my truck.