Hi all.. I got a code for downstream O2 heating circuit. both banks.. 2005 Lr3 140k miles.
Can't seem to unscrew the one side I tried-pass side.. I can get to it with an open ended 7/8 . .(maybe 22mm is better).. it feels like its going to slip.
I have a purpose made socket tool (3/8 drive, offset kind). Cant get it on. and with the open slot, I bet it'll slip also..
going to cut the wires and try a real socket or the box end..
Any suggestions?
Thanks
Can't seem to unscrew the one side I tried-pass side.. I can get to it with an open ended 7/8 . .(maybe 22mm is better).. it feels like its going to slip.
I have a purpose made socket tool (3/8 drive, offset kind). Cant get it on. and with the open slot, I bet it'll slip also..
going to cut the wires and try a real socket or the box end..
Any suggestions?
Thanks
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abran
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I have no looked into the O2s on the LR3 yet, but on most vehicles the downstream are not heated. And in most cases if O2 sensors are showing a fault at both banks, there is another issues elsewhere. Such as a vacuum leak.
Quote:
thank you guys.. good question.. I am NOT sure its the O2 sensors.. Originally Posted by DakotaTravler
I have no looked into the O2s on the LR3 yet, but on most vehicles the downstream are not heated. And in most cases if O2 sensors are showing a fault at both banks, there is another issues elsewhere. Such as a vacuum leak.
codes: P0056 .. heater control circuit bank2 sensor 2
P0036 heater control circuit bank 1 sensor 2
P0406 Exaust Gas recirculation sensor A circuit high
P0402 Exaust Gas recirculation flow excessive detected
the signal from both downstream sensors was 0.000mA ..steady 0.. The upstreams were like 0.02-4 mA range..
All according to my iCarsoft...
so .. ideas.. ?
TIA
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Sounds like a possible bad EGR valve. Which would make total sense why the O2 sensors are out of range. Need to verify the EGR sensor condition/connections.
Quote:
Thanks.. How do I check that on LR3, do you know? Also.. both O2 sensors show exactly 0mA.. as if disconnected or shorted or dead, not failing (unless they get clipped at 0.0?) .. Yes.. I agree it's more likely it's elsewhere, rather than both sensors failing coincidentally. OK. .Ill go check the EGR. will gladly accept more suggestions Originally Posted by DakotaTravler
Sounds like a possible bad EGR valve. Which would make total sense why the O2 sensors are out of range. Need to verify the EGR sensor condition/connections.
thanks
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Are you certain the codes are correct for downstream, post-cat?
The post cat sensors should appear dead. With the vehicles I am familiar with, the downstream only monitor catalytic operation and fault when there is an issue with the cats failing or not coping with a major fault. And again, not usually heated since they don’t assist in regulating the mixture. So the slowly heat up in the exhaust stream. Upstream are heated to get them to operating temp and thus provide feedback on the fuel mixture.
As for the EGR operation, I’m not familiar with it on the LR. But it sounds stuck open.
The post cat sensors should appear dead. With the vehicles I am familiar with, the downstream only monitor catalytic operation and fault when there is an issue with the cats failing or not coping with a major fault. And again, not usually heated since they don’t assist in regulating the mixture. So the slowly heat up in the exhaust stream. Upstream are heated to get them to operating temp and thus provide feedback on the fuel mixture.
As for the EGR operation, I’m not familiar with it on the LR. But it sounds stuck open.
took off the egr valve.. tested that its not stuck open .. and that it somewhat holds vacuum.. except I hear hissing at the diaphragm. I soaked it, cleaned it, reinstalled it, cleared codes. Codes came back in 20 sec..
So Im going w. a bad egr valve..
So now.. an EGR valve for a LR3 v6 (EGV1178) is $193 .. and for a the same 4.0v6 in a ford (EGV1055) is 85.13 , from the same parts place. .wtf.. same ford v6.. looks identical, of course..
what say you all?
So Im going w. a bad egr valve..
So now.. an EGR valve for a LR3 v6 (EGV1178) is $193 .. and for a the same 4.0v6 in a ford (EGV1055) is 85.13 , from the same parts place. .wtf.. same ford v6.. looks identical, of course..
what say you all?