code P1151
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Elder User
Joined: Nov 2007
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From: Canada, ON New Market
code P1151
I recieved a check engine light on may way to work on monday, checked what code it was and P1151 is the player this time.
P1151 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 2
-Did a search on the forum it seems that changing the O2 sensors solves the problem...
I ordered 2 O2 sensors from ford the same day picked them up the next, installed one driver's side which should be bank 1, next day I changed the passanger side bank 2.
So now were friday and the code still hunt's me, I pulled the O2 sensor on bank2 and it's white
. So I pulled the tune (which is tow) and still running it on 91 with still some sounds of ping
.
My plans are to test the wires for the O2 sensors next, then fuel filter, and finaly moving on to feul psi test. Only problem with all of this is that it's cold as heck out side
P1151 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 2
-Did a search on the forum it seems that changing the O2 sensors solves the problem...
I ordered 2 O2 sensors from ford the same day picked them up the next, installed one driver's side which should be bank 1, next day I changed the passanger side bank 2.
So now were friday and the code still hunt's me, I pulled the O2 sensor on bank2 and it's white
. So I pulled the tune (which is tow) and still running it on 91 with still some sounds of ping.My plans are to test the wires for the O2 sensors next, then fuel filter, and finaly moving on to feul psi test. Only problem with all of this is that it's cold as heck out side
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From: Long Island USA
Before spending money, check two things.
Check for a vacuum leak, especially at the plumbing for the PCV, particularly the elbow at the throttle body.
Clean the MAF - a dirty MAF will give you a lean code. It can generate one lean code in one bank, or both.
Check for a vacuum leak, especially at the plumbing for the PCV, particularly the elbow at the throttle body.
Clean the MAF - a dirty MAF will give you a lean code. It can generate one lean code in one bank, or both.
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Joined: Jan 2008
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I had the same code. It ended up being that two fuel injectors on that bank were stuck open so it was super rich that caused the code (the code is saying the computer is as far lean as it can go with the fuel map and the O2 sensor is staying rich). When I bought the truck I replaced the fuel filter because it was so clogged and psi was low. Guessing because of the lack of maintenance let the injector get dirty.
Check the injectors for an audible click with a stethoscope.
Check the injectors for an audible click with a stethoscope.
Thread Starter
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Elder User
Joined: Nov 2007
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From: Canada, ON New Market
I had the same code. It ended up being that two fuel injectors on that bank were stuck open so it was super rich that caused the code (the code is saying the computer is as far lean as it can go with the fuel map and the O2 sensor is staying rich). When I bought the truck I replaced the fuel filter because it was so clogged and psi was low. Guessing because of the lack of maintenance let the injector get dirty.
Check the injectors for an audible click with a stethoscope.
Check the injectors for an audible click with a stethoscope.
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Joined: Jul 2002
Posts: 42,561
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From: Long Island USA
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I think he was saying strategic fuel trim between bank 1 and 2 are different. They should be around the same reading on a good running motor. Bank 2 is running pretty rich and the computer is trying to lean it with the 1.14 reading. So he should be checking cylinder 6 -10's fuel injectors. Same side I had a problem on.
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Elder User
Joined: Nov 2007
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From: Canada, ON New Market
The weather was rather warm this weekend so I got out to diagnosing my code, I proped the live wire between the door and a pillar with stft's showing and started pulling injectors one by one, and if I'd be damend it was cylinder number 9 (the same cylinder I changed the burnt exhaust valve out last summer) now I know there is a 1 in 10 chance that the same injector last year was reinstalled on cylinder 9 but unlikely. Which leads me to believe I have a short or in need of a new computer
the code is now gone with the 9 injector disconnected tables evened out to .98 at idel
the code is now gone with the 9 injector disconnected tables evened out to .98 at idel
New User
Joined: Jan 2008
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Before chasing wires I would change out the fuel injector with either a new one or switch it and see if the problem moves to the other cylinder. It would save a lot of headaches. I would plug the injector back in though since the fuel helps cool the cylinder.
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Elder User
Joined: Nov 2007
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From: Canada, ON New Market
i got a chance today after work to swap thw injectors, switched cyl1 with 9 and it still ran rich disconect it an the feul tables return to normal. Now i'am hoping for a short some were, you guys would happen to know thw color code of the wire at the pcm clip would yea? If this isn't the problem then the computer is the only veriable left
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Elder User
Joined: Nov 2007
Posts: 528
Likes: 1
From: Canada, ON New Market
i got a chance today after work to swap thw injectors, switched cyl1 with 9 and it still ran rich disconect it an the feul tables return to normal. Now i'am hoping for a short some were, you guys would happen to know thw color code of the wire at the pcm clip would yea? If this isn't the problem then the computer is the only veriable left
So I'am going to check for spark, if thats not the problem then a CR check will be next. Personally I seriously think its time for a new motor
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From: Long Island USA
Skoda, can you put a meter on the fuel injector connector while it's running? (disconnecting the fuel injector of course)
With the meter on AC, you should see some voltage, if it's a DVM, it should just show 12V or close to it I'd think.
If it doesn't show anything on AC, switch to DC - if it shows 12V or higher, the driver in the PCM is bad. Meaning, it's shorted.
Here's the EVTM section for the injectors from 2001. Not sure if they are the same for a '99:
With the meter on AC, you should see some voltage, if it's a DVM, it should just show 12V or close to it I'd think.
If it doesn't show anything on AC, switch to DC - if it shows 12V or higher, the driver in the PCM is bad. Meaning, it's shorted.
Here's the EVTM section for the injectors from 2001. Not sure if they are the same for a '99: