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Discussion Starter #1
HI

Occasionally (almost every day) my JTS throws up two Lambda errors:

P0134 Lambda Sensor Bank 1 (Pre Cat)
P0154 Lambda Sensor Bank 2 Slow Response (Pre Cat)
both with "Fault Symptom: No Signal"

As clearing them makes them go away for a while, I am assuming I have a dodgy connection somewhere, and they are not failing per say. Its also funny that its always the same two, and both do so at the same time!

So before I go on a wild goose chase, where should I start looking for connection problems ?
 
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Unplug and start by using some contact cleaner and see what happens.
Also check to see if they are non genuine as it maybe they have been replaced with universal ones and the wiring needs redoing should be fairly apparent ? Does sound like a bad contact though .
Probably best to disconnect the battery first but if you need one don't forget the radio code may be needed when you reconnect
 

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I get the same issues approx every 150 miles, P1133 and P1153. reset and all is good till next time around......:(
 

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Discussion Starter #4
Unplug and start by using some contact cleaner and see what happens.
Also check to see if they are non genuine as it maybe they have been replaced with universal ones and the wiring needs redoing should be fairly apparent ? Does sound like a bad contact though .
Probably best to disconnect the battery first but if you need one don't forget the radio code may be needed when you reconnect
Yeah, but unplug what and where ? :)
I have cleaned up the battery plugs and leads with a wire brush, and I have done the same for the relays at the front of the battery, but that has not done the trick...
 

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2 big (20 odd wires) connector blocks behind the inlet manifold (on a jts anyway), try cleaning them up and scraping the connectors to cut through any oxidation. get a pointy thing and try to reduce the gap on the female connectors to create a better contact (don't go crazy though you want to be able to close the block up again!)
See if your problem goes away, I did this and cured loads of errors- my jts was going into limp mode before - I was getting Knock sensor errors, Lambda, coil pack, missfires and others. did this block clean up and it all stopped! didn't cost me a penny - ,...That was about 2 months ago. Just 2 days ago i've started getting the Lambda sensor errors again. So as one of my big blocks was already soldered by previous owner, I'm going to solder the other one... I want to solder the Lambda blocks too either side of the fan but the block has a piggy back from some weird extra black bit - whats that? is it important?
 

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The connectors for my lambda sensors have already been worked on by the previous owner, their method was to use some kind of sealant in the connector blocks where the wires enter the connector to keep the wires secure and stop moisture getting in. Since then the only thing I've done is spray some WD40 into the plug side of the connectors and this solved the very intermittent MCSF I was getting. These plugs are the ones just in front of the radiator, and I believe there is 2/3 of them.

I've not looked at the big plugs behind the engine, I will check those also.

Mark
 

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My Lambda connectors had that grease in them, I don't know if thats where the errors were coming from, but its to much of a coincidence to ignore that when I did the big block all the trouble stopped.
I read all over here people suggesting soldering the big connector blocks, after my personal experience of the problems caused I would say the same now... i'll solder and then see.
Anyone know if the central locking and windows draw power through the bulkhead connector blocks? my fuses are fine but no front window power and no central locking?!
 

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My Lambda connectors had that grease in them, I don't know if thats where the errors were coming from, but its to much of a coincidence to ignore that when I did the big block all the trouble stopped.
I read all over here people suggesting soldering the big connector blocks, after my personal experience of the problems caused I would say the same now... i'll solder and then see.
Anyone know if the central locking and windows draw power through the bulkhead connector blocks? my fuses are fine but no front window power and no central locking?!
Update on this... soldering the block at the bulkhead has fixed my issues!
The problem I had with my windows, speakers and central locking was the wiring connector block in the drivers door hinge - clean and reconnect a few times sorted it.
 

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Update on this... soldering the block at the bulkhead has fixed my issues!
The problem I had with my windows, speakers and central locking was the wiring connector block in the drivers door hinge - clean and reconnect a few times sorted it.
Hi alfabum,
What were your symptoms when you cleaned the connector in the door ?. My radio gets interference when I press the brake pedal, only seems to happen when warm though
 
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