19 replies to this topic

[nomoreheroes]

Hello,

 

what is the definitive guide to lambda sensors here?

 

Presuming everything was correct and operational before the swap (according to MEMS Diag). What could have caused the new sensor to fail? By correct, I mean the lambda signal was oscillating as it should at idle. By faulty, I mean the same signal with a hot or cold engine is fixed at 435mV at idle.

 

At this time I have also had the inlet manifold and coolant temperature sensor replaced. Along with new bolts on the cat. I only changed the lambda sensor as it was old and within reach.

 

Specifically what are the exact conditions for the lambda sensor to run in closed loop operation? Information on this website and across the internet is unclear.

 

Two relays activate the lambda sensor yes? One in the black relay box by the ECU and a yellow one on the other side of the engine bay.

 

Thankyou for your time.

 

Elliott.

Edited by nomoreheroes, 26 March 2021 - 08:29 PM.

[genpop]

"What could have caused the new sensor to fail?"

 

It is the wrong one.

No internal connection to ground.

Genuine bosch part number is 0258 003 193

Edited by genpop, 27 March 2021 - 07:54 AM.

[nomoreheroes]

Thankyou for the reply Genpop,

The MHK10004 I purchased was sold as suitable for the SPI mini. I'd read many times it was the correct part. Is this in fact 'incorrect information'?

I appreciate the Bosch part is the definitive part but I thought MHK10004 was a worthy alternative.

Elliott.

Edited by nomoreheroes, 27 March 2021 - 09:43 AM.

[genpop]

I do not know which ecu you have. The  MHK may work on the 1.6 but the 1.3 definitly needs the Bosch one. ( I have no 1.6 nor 1.9 )

This is the schematic if the lambda probe doesn`t work like that you will have no oscylating signal.

Attached Files

•  Sonde.JPG   44.32K   6 downloads

Edited by genpop, 27 March 2021 - 11:50 AM.

[nomoreheroes]

Hello Genpop, thankyou once again. The ECU is the 1.3 version. I'm surprised it's not widely known (I'm surprised I've not been able to find the information) that the 1.3 ECU will only accept a genuine Bosch lambda sensor. Is there a suggestion there that I could add a wire from the slate grey wire to the ground/sensor body/engine to get it working?

 

Elliott.

[genpop]

No suggestion, but it will work.Next owner of the car will throw away this wire and have the same problem like you!

Hundres of people state you need the Bosch one but there are always some guys who want to invent a new car.

[humph]

Have you checked the wiring? I chased an intermittent problem for ages until i got lucky one day when it was playing up and located a broken wire to the O2 sensor. The loom rubs against the bulkhead bu the throttle body.

[nomoreheroes]

No suggestion, but it will work.Next owner of the car will throw away this wire and have the same problem like you!

Hundres of people state you need the Bosch one but there are always some guys who want to invent a new car.

'Next owner' - that's not likely to happen.

 

Of the hundreds of people, no one has made the link between the Bosch sensor and the 1.3 variant ECU.

 

I'll have a go with a temporary lead for this lambda sensor.

 

Thankyou.

[nomoreheroes]

Have you checked the wiring? I chased an intermittent problem for ages until i got lucky one day when it was playing up and located a broken wire to the O2 sensor. The loom rubs against the bulkhead bu the throttle body.

Hello Humph, I've checked the wiring in as much as the system was functional before I swapped the lambda sensor. I presume nothing was disturbed during it's replacement.

 

Thankyou.

[nomoreheroes]

Genpop,

 

Linking the Slate wire to the ground (the black wire on the top of the wiper motor in this case) has not improved matters.

 

I am stuck again.

 

Elliott.

Edited by nomoreheroes, 06 April 2021 - 10:53 AM.

[genpop]

where is a wiper motor?

light green coming from the ecu-  plug and socket - slate to the lambda sensor- +slate to ground.

Or take the Bosch one.

[nomoreheroes]

Hello Genpop,

 

the wiper motor is to the right in the opposite corner of the engine bay.

 

I'll try your suggestion.

 

Elliott.

[nomoreheroes]

I just did a continuity check on the lambda sensor. The wiper motor earth, engine stud / sparkplug, the body of the lambda sensor and the slate grey wire from the lambda sensor are all connected to each other. So it should work.

Elliott.

[genpop]

what is mems diag telling? there is an other diagnose tool in the android software pool from andrew jackson  memsfaultcodereader!

[nomoreheroes]

The system hasn't changed since I checked it at the weekend. After adding the wire, the lambda voltage is now 980mV (constant), from 435mV before the mod. The MAP sensor looks functional. The engine temperature had risen to 34 degrees while the lambda voltage was constant.

I'll have another look at the diagnostics tomorrow. Does the engine need to be warmer for the voltage to start oscillating? I swear the voltage of the previous sensor was oscillating from cold.

The supplied part is an Intermotor 64007. Listed as a like for like replacement of the Bosch 0258 003 193 and MHK10004.

Elliott.

P.S. I have MEMS Diag and Rover MEMS on my phone.

P.P.S. Looking at the screen grab from the other day it looks like it was in closed loop. It's just at the bottom of the screen grab, but the field says '1' now and not '0'.

Edited by nomoreheroes, 06 April 2021 - 08:53 PM.