CEL on, N75 error.
07-30-2007, 04:46 PM
#1
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CEL on, N75 error.
Hi,
Been a while since I've posted. Been busy with work / other cars...
Driving the car home from work, CEL came on. When I arrived home I hooked up vag-com and saw the errors below.
17539 - Oxygen (Lambda) Sensor; B2 S1: Internal Resistance too High
P1131 - 35-10 - - - Intermittent
17956 - Boost Pressure Regulation Valve (N75): Open Circuit
P1548 - 35-10 - - - Intermittent
I went ahead and order a universal 4-wire from ECS, and an N75 valve. However, I'm having second thoughts about the N75. Any chance that it's not the valve, and just a host leak?
Anybody?
Thanks,
Tom
Been a while since I've posted. Been busy with work / other cars...
Driving the car home from work, CEL came on. When I arrived home I hooked up vag-com and saw the errors below.
17539 - Oxygen (Lambda) Sensor; B2 S1: Internal Resistance too High
P1131 - 35-10 - - - Intermittent
17956 - Boost Pressure Regulation Valve (N75): Open Circuit
P1548 - 35-10 - - - Intermittent
I went ahead and order a universal 4-wire from ECS, and an N75 valve. However, I'm having second thoughts about the N75. Any chance that it's not the valve, and just a host leak?
Anybody?
Thanks,
Tom
07-30-2007, 07:06 PM
#3
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Did you unplug the N75 with the key on at anytime since you last cleared codes?
N75 doesn't look like a hard fault and will not turn on the CEL anyway. The O2S turned it on, replace that, clear codes, and wait to see if the N75 code comes up again; but it was intermittent so it may not.
Come on mike@streamline, diagnose then replace. Didn't I teach you anything
Come on mike@streamline, diagnose then replace. Didn't I teach you anything
07-31-2007, 04:49 AM
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Re: Did you unplug the N75 with the key on at anytime since you last cleared codes?
Thanks. Didn't know if N75 would throw CEL or not.
I cleared codes last night. I'll replace the 02 sensor first just to try and nail it down. I didn't try diconnecting the N75 with ignition on, I will try that. It'd make sense that it would throw an open circuit code if I did disconnect.
B2 S1 sensor is driver's side front, correct? Not really looking forward to it, I haven't had to do anything except change fluids / brakes / rotors for quite some time.
Since you're reading this - are all 4 O2 wide band, or just the front? (just curious)
I cleared codes last night. I'll replace the 02 sensor first just to try and nail it down. I didn't try diconnecting the N75 with ignition on, I will try that. It'd make sense that it would throw an open circuit code if I did disconnect.
B2 S1 sensor is driver's side front, correct? Not really looking forward to it, I haven't had to do anything except change fluids / brakes / rotors for quite some time.
Since you're reading this - are all 4 O2 wide band, or just the front? (just curious)
07-31-2007, 08:55 PM
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If you disconnect N75 with key on and plug back in, it will give intermittent open circuit. B2S1 is
drivers side front and it is the more difficult one. None of B5S4 O2 sensors are wideband.
08-04-2007, 07:34 AM
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Re: If you disconnect N75 with key on and plug back in, it will give intermittent open circuit. B2S1
Parts just arrived, I just have to get the 2002 out of the garage so I can do this.
You sure the pre-cat aren't wideband? Seems like Audi wouldn't be able to tune well for varied barometric levels/fuel quality without wideband.
Also, I was just comparing comparing to the Bosch WB02 used in an Innovate LC-1. Looked like the same thing.
You sure the pre-cat aren't wideband? Seems like Audi wouldn't be able to tune well for varied barometric levels/fuel quality without wideband.
Also, I was just comparing comparing to the Bosch WB02 used in an Innovate LC-1. Looked like the same thing.
08-04-2007, 10:15 AM
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Pretty sure they aren't wide-band, they are only 4 wire sensors whereas wideband are generally 5.
The sensor housings may look similar but the WB wiring should have an extra red or yellow wire? Good luck!
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