Safe to run with lambda probe disconnected?

[pphilpot]

Hi all

Just a quickie – I'm still on the hunt for a solution to my 18. petrol hesitation problems - I tried disconnecting the lambda probe, but on my 406 the engine management light comes on.

Is it safe to run the car with the lambda probe disconnected and (because of this) the engine management light being on? In the thread "FAQ - 406 D8 petrol (Excl. V6) running and starting problem" it says that the engine management light won't go on, but I guess mine is a D9 (late 1999).

Thanks in advance

Cheers

[maxxymilian]

No problem with running with the probe disconnected. The fuel consumption will go up a bit though... The damn things need to be replaced every 10 years or so.

[pphilpot]

Great, thanks maxxymilian, I'll give it a few days disconnected and see if it clears the problem!

Cheers

[pphilpot]

OK, next question. Can anybody help me to let me know what tool I need to order to get the lambda sensor off, and fit a replacement. It's in an awkward position for my spanner as there's no space for movement. Oh, I'm working from the top here, as it appears to be easier from the top.

I'll probably buy the tool online, so I just need the size and name.

Cheers

[pphilpot]

OK, I've guestimated that it needs a 22mm ring spanner (which I don't have). So I'm going to get one which I'll cut the open end off, and possibly grind down the shaft to enable a 15mm pipe to go over it. *Hopefully* I'll be able to move the sensor enough to move the ring spanner 1 notch at a time...

[maxxymilian]

You are aware that you have two lambda probes right, one is on the cataltic converter. Just giving you a hint to think about....

[pphilpot]

Thanks maxxymilian, this hesitation problem is doing my head in a little

Going by the post that has been 'stuck' at the top of this section, I've disconnected the front lambda probe and the engine is running well (albeit with the engine management light on), and not hesitating. Therefore I hope that replacing that probe will cure the problem (as suggested by the above thread). Of course it could also be the coolant temperature sensor or the MAP sensor, but I guess I'll find out once I fit a replacement lambda probe!

Seeing that I only paid £450 for the car, I'm kinda being tight on fixing this problem so I'm doing it step by step:

Replaced the stepper motor (£20) - cured erratic idle
Replaced coil pack (£18- good used part) - made no difference
About to replace the front lambda probe (£30 - el-cheapo Chinese jobbie. I know, I know...) - we'll see

Damn, £68 already. Still, I could have paid £40-£50 for a code read, and still have been none the wiser!

Cheers