DII O2 harness

[BackInA88]

So after replacing my injector o-rings and clearing up all my lean codes I now have a P0135!
Oxygen O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)

All my lean codes are gone and I swapped the O2 sensor for a good spare I had but I still have the code.

So I'm wondering is the OS harness running to the O2 on the drivers side long enough that I may have pinched it under the coil mounting bracket and grounded one of the O2 heater wires when I put everything back together?

Or should I look elsewhere?

 

[Rockbeard]

really the only thing that most always causes a lean condition is a vacuum leak, or in rare instances low fuel pressure. go over your handy work to try and find the vacuum leak. a smoke machine helps a ton if you have access to one. as far as suspecting a pinched wire, look at the voltage of the sensor with scan tool and snap the throttle, it should fluctuate up and down. if it stays low voltage all the time, the leak must be bad or is a bad sensor. hope this helps, good luck

 

[Rockbeard]

dude, i'm sorry for going on about the lean condition since you fixed that already...duh. bruising a wire is always possible, so do check the harness. then check for supply voltage to the sensor and all the other stuff. If it's not heating up fast enough it might be a power supply thing or more often than not, a lazy sensor. can you swap it to the other side and see if the code changes? if so, you will have a lot more to go with. good luck

 

[discostew]

So after replacing my injector o-rings and clearing up all my lean codes I now have a P0135!
Oxygen O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)

All my lean codes are gone and I swapped the O2 sensor for a good spare I had but I still have the code.

So I'm wondering is the OS harness running to the O2 on the drivers side long enough that I may have pinched it under the coil mounting bracket and grounded one of the O2 heater wires when I put everything back together?

Or should I look elsewhere?

You should make sure a terminal didn't back out of the plastic connector housing. That happens a lot on these o2 connectors. The heater circuit is easy. Measure the resistance accross the heater and compare it to the other side sensor. Then check battery voltage and ground on a cold start.

 

[BackInA88]

You should make sure a terminal didn't back out of the plastic connector housing. That happens a lot on these o2 connectors. The heater circuit is easy. Measure the resistance across the heater and compare it to the other side sensor. Then check battery voltage and ground on a cold start.

That's a great idea I didn't check the pins on the harness side connector, I'll do it tomorrow.
It makes a lot of sense since I figured it had something to do with what I worked on and I couldn't see how I could have pinched the harness. So I thought before I pulled the plenum again I would run it by DiscoWeb.

What pisses me off is I never touched the damn O2's but I guess moving the harness all over pulling the plenum and and coil packs twice may have tugged them back out of the housing?

First time to changed the injector o-rings and again when 3 of them were leaking on the rail?
Pulled then off and stuck them back on and now no leaks? Must have been some crud in the cups?

So drive it around and fuck if I don't get a code I have never had!

These rigs really know how to piss me off sometimes.




Steve

 

[KyleT]

Look for oil in the connector housing, pull the pins and clean them very good.

 

[BackInA88]

Update follow up

So I cleaned the connectors and checked continuity on all the wires running from the Bank 1 Sensor 1 plug to the the plug on the ECM.
Found no problems and none were grounded.
Pulled my spare O2 back off and checked the heater wires and only got 2 ohms across them just like the old one.
Everything I found on the internet said it should be 6 ohms.

So I bought a new Bosch O2 15175 direct fit.
Like a bonehead I didn't check the new one to confirm the 6 ohms before I put it in!:banghead:

Drove it for a 1/2 hour and no codes popped up.
I did notice that it did flash "OL-fault" on my scanner when it switched to CL.
With the old O2's the OL-fault stayed up.
I'll need to get a few drive cycles on it to see if it is truly fixed.

Thanks
Steve

 

[discostew]

You say none of the wires are grounded? Red/black wires should all be getting grounded by the ECM. Might just be with engine running since BMW likes to go over the top with shit.

 

[BackInA88]

You say none of the wires are grounded? Red/black wires should all be getting grounded by the ECM. Might just be with engine running since BMW likes to go over the top with shit.

Only grounded when plugged into the ECM I checked them with the harness unplugged.

 

[discostew]

Perfect

 

[BackInA88]

Well just an update.
I finally got around to really digging into this, don't drive the truck much.

I had checked everything going back to the ECM and everything was good so this left me scratching my head.
Couldn't be the brown/pink 12 volt supply wire, right?
As it has all kinds the other sensors using that 12 volt wire and they were all fine and not throwing any codes.

Wrong!

Apparently the 12 volt supply for Bank 1 Sensor 1 has it's own feed wire back to fuse 2.
It goes through the grey connector between the under hood fuse box and the firewall (bulkhead).
It had a corroded pin in that connector.
Pulled the pins on both sides of the connector and cleaned them up and gave the female side a little squish to make it tighter and all seems to be good. After a couple drive cycles and no codes.

I guess the other sensors the use the brown/pink are in the harness that comes across the front of the engine?
So where does the brown/pink 12 volt supply wire for bank 2 run? I never had any faults with that one?
Another separate wire running thru some other fucking connector?

Well I guess Land Rover was trying to teach me the same lesson again, never assume anything.