Replacing M52 lambda sensor

[RKB]

Just wondering whether this is a straight forward job and the right part as I've seen a few.

Cheers

[Brianmoooore]

As long as the old one cooperates when you unscrew it, then it's straightforward. It's a perfectly ordinary lambda sensor, and most 'universal' ones only come with a short lead attached, plus some crimp joiners, which you use to connect it to the bulk of the lead and plug from your old one.
You haven't said why you're replacing it, but be aware that most code reading equipment that suggests the lambda sensor is at fault is incorrect. In most cases (but far from all) the sensor is doing its job, and reporting the effects of a fault elsewhere, as was the case with the last M52 I worked on about a month ago. Fault codes suggested lambda sensor, fault was MAF.

[RKB]

Ive not had a code reader on there but replacing as the car stinks of fuel, pretty badly.

I did clean the MAF which did help it, but im getting poor economy (driving sensibly) as well...

Cant really think what else it could be?

[Brianmoooore]

Get yourself one of these: https://www.ebay.co.uk/itm/ELM327-V2-1- ... Sw2XhfEltX Not necessarily from this supplier - there are dozens on ebay, and download a free relevant app. onto your 'phone., and see what it comes up with.
Simple test for the MAF is simply to unplug it. The ECU will substitute a default signal, and the car will run almost as good as it will with a working one. Certainly better than it will run with a damaged one. The difference is so small that it's very likely that some MAFs sold on ebay have no working parts at all.

[RKB]

I haven't got round to getting a reader but did disconnect the MAF and the car began to hunt but stayed on.

Guessing the MAF is doing something whilst connected.

I'll get a reader ordered, think mine is still OBD1.

[RKB]

Tried one of those Bluetooth obd connectors, unfortunately it couldn't connect to the cars ECU.

Fitted a new MAF last night, not sure if it's made much of a difference unless it's meant to take a few drives to calibrate?

[Brianmoooore]

From another current thread, re fitting an OBD II socket:

"DanThe
Best Car & Mod-Master Winner 2009
Posts: 27990
Location: Staffs
Fri Jul 31, 2020 4:59 pm

I just used Earth, Ignition and the K-line White/Violet, no reason why the adaptor shouldn't work TBH

Co founder of CR24vTM"

I didn't mean to suggest there was anything wrong with your MAF. That was just an example from a diagnostic session I had a few weeks ago, where the codes incorrectly suggested a lambda sensor fault.
The point ! was making is that diagnostic codes need to be intelligently interpreted, just just "computer says lambda sensor, so replacement lambda sensor needed".
First thing I'd be checking out for a rich mixture (spark plugs black?) is the coolant temperature sensor, but I'd be testing it, not randomly replacing it.

[RKB]

Was a punt with the mAf as I've no way of testing it.

I'm going to revert back and return the new one as faulty.

Did try the Bluetooth obd2 to a OBD1 cable.

Would be ideal to get a reader on.

[Brianmoooore]

Was a punt with the mAf as I've no way of testing it.

Testing a MAF: If the car runs better, almost as normal, and the majority of whatever problem you have goes away, with the MAF unplugged, then it's probably faulty.
If unplugging it makes almost no difference, then it's probably good.

[RKB]

I disconnected it initially to test, which the engine then started to hunt almost wanting to turn off.

This makes me think it's an lambda sensor.

[RKB]

Found some cracking in the intake boot, will replace to see if that helps.

[Brianmoooore]

Found some cracking in the intake boot, will replace to see if that helps.

It's the sort of thing that would cause hunting.

[RKB]

A little update;

Replaced the lambda and the intake boot...it seemed slightly better but now it's really bad in terms of stinking of fuel.

Any ideas of what else I can do, my next move would be to replace the MAF but should be checking for leaks.

Cheers

[Brianmoooore]

Stinking of fuel from where?

[RKB]

Just sat in the driver's seat with the window open. A little too strong - doesn't smell in the cabin.