48 replies to this topic

[ski]

Thanks Genpop will have a go this evening. If its not warming up, I guess it would be the connection possibly on the other 2 wires. Or the relay which controls the heating. Where is the relay located or is it part of the ECU? 

[pete l]

I had a high lambda reading on mine, got a new genuine Bosch one and it was fine after.

[Wiggy]

Ok, just been out.
 
STONE COLD 1ST START:

RPM = 1260

CAM SIGNAL = GOOD

CRANK SIGNAL = GOOD

STEPPER POSITION = 80

INJECTOR 4 PULSE WIDTH = 1.67

INJECTOR 2 PULSE WIDTH = 1.65

COIL 2 CHARGE = 1.48

COIL 1 CHARGE = 1.50

THROTTLE SWITCH = OFF

THROTTLE POSITION = 4.2

MAP SENSOR = 40.6

INLET AIR TEMP = 9

ENGINE COOLANT TEMP = 17

 

ENGINE HOT:

 

RPM = 891

CAM SIGNAL = GOOD

CRANK SIGNAL = GOOD

STEPPER POSITION = 14

INJECTOR 4 PULSE WIDTH = 0.75

INJECTOR 2 PULSE WIDTH = 0.77

COIL 2 CHARGE = 1.55

COIL 1 CHARGE = 1.53

THROTTLE SWITCH = OFF

THROTTLE POSITION = 4.8

MAP SENSOR = 30.8

INLET AIR TEMP = 46

ENGINE COOLANT TEMP = 96

 

Didn't include the Oxygen sensor, as the ACR4 doesn't read it properly.

 

Spec:

 

John Cooper Big Valve Head

1.5:1 Rockers

Kent 274i Camshaft

LCB

 

No fuelling modifications at all.

Edited by Wiggy, 04 February 2019 - 09:08 PM.

[ski]

This is a new sensor, none genuine though. Purchased from minimine?.

Thanks wiggy will compare with mine now, I'm away on work.
I didn't have much time last nite but I've completely cut the lambda connector out and stripped the 2 thicker wires that are meant to supply the lambda heating element. I only quickly checked but with ignition on these seemed to give only 300-400mv. I thought it should be a constant 12v?

Before cutting I also left ignition on and then held the back of the sensor and couldn't feel any heat.
There is 2 yellow relays to the left of the servo, one wire has been snagged and is stripped of insulation for 4-5"! The copper also looks oxidised.

I also didn't realize the sensor breaths through the stainless wire, I will cut the soldered parts off and buy some proper connector's.

Edited by ski, 05 February 2019 - 10:59 AM.

[genpop]

According to the wiring diagramm, the blue wire should have 12 V to the black wire if you have a voltmeter connected. These two wires have to be connected to the two white wires on the lambda sensor.When ignition is on the sensor should warm up then.The other colors connect accordingly.

[pete l]

My first lambda was a minispares one, it failed the french MOT, got a new genuine BOSCH one and it passed.

[ski]

Checked the wires for the Lambda heater with ignition on, engine off, 100% no voltage there at all, so ill guess I will have to strip the loom back a bit and see whats going on. 

 

I pulled the plugs and did a compression test, 1&2 were a bit brown and dusty. 

Cylinder 1 - 175 psi, 2- 140psi, 3- 155psi, 4- 160psi. 

 

This is cold start- 

 

 

 

 

 

 

And hot, does seem to be warming up quickly the rad fan is kicking in at 105c coolant temp. 

 

Attached Files

•  cold.PNG   213K   11 downloads
•  warm.PNG   219.7K   9 downloads

[Wiggy]

I'm not the best at actually interpreting the data, but I think you need to reindex the stepper motor. You can do this on the ACR 4, but I'm not sure about your gear. Check through all the menus. Especially because you've played with the throttle stop.

The MAP sensor reading on yours (when hot) is higher than mine. And also the idle is too high. And the stepper position is different.

I'm not sure that the oxygen sensor heater not operating would make much difference once the engine is hot. But it'd obviously be desirable for to be working.

[genpop]

 Unbenannt.JPG   74.24K   9 downloads

 

I think your datas are good for the moment .But you still have to check why your lambda sensor is not working.When lambda is working , then you can close the throttle a bit more until idle is at 875.With that the the idle deviation will decrease( should be at 0 and factory idle setting  is momentary idle minus deviation) after that the IAC steps will increase to about 10 to 15.And map will decrease as well.

I don't know why your pscan says  engine is not cranking !

 

 

 Unbenannt2.JPG   51.33K   9 downloads

 

But your main problem is your lambda sensor.I attached the second picture.There you see the plus for the sensor heater coming from the main relais pack connector nr C157-2, its the blue/red wire in the car.Between that and black you should have 12V. Check line continuity between relais pack and sensor and between sensor-grey (s) and C158-27 as well as sensor light green with grey (lgs) and C158-28.

 

ONLY WHEN YOUR LAMBDA SENSOR VOLTAGE IS SWINGING BETWEEN 100 and 900 mv yyythe engine will switch to closed loop  and only then it is worth interpreting all values!

 

[genpop]

Addionaly you may check continuity between C 158-20 from ecu to c154-5 at the relais-pack. Your pscan says oxygen heater = on, so there should be minus.

[ski]

Thanks Genpop, i will start digging through the loom and report back. 

 

I pulled the main relay pack and found a big greased thumb print on the front of the connector!. 

I need to remove the ECU and then open the loom a bit so its easier to trace back. 

[ski]

Had a quick look today, I've checked the 2 heater wires, one back to the relay pack and the other to ground both good.

I pulled the relay pack out, all coils are about 69ohm, one on the top right has some burning on the contacts.

I then pulled the ECU and both plugs to check the sensor wires again fine, but I did find more black grease all over the ECU connectors and finger prints!

Need to go back and check C 158-20 from ecu to c154-5 though. That could be bad in which case the heater not working or the relay pack could be bad. I think the sensor it's self might have been dead on arrival so will order up a generic Bosch one, which is what I had in the first place but swapped it for one with the correct connector (but a cheaper brand I've not heard of).

[genpop]

Hi, is the engine running in closed loop now? What was the fault? Do you have new values ( log-file)?

[ski]

Not had chance to put it back together yet!.
Going to take next Friday off work and get to work on the mini.

All wiring is fine.
Genuine Bosch lambda to go on, and I've repaired the lambda plug on the harness.
So fingers crossed.

[ski]

Hi all an update, the voltage still doesnt seem correct on PC scan but its saying that closed loop control is on. 

Its idling much better, ive also fitted another relay pack. 

I repaired the loom plug and fitted a genuine Bosch sensor. 

 

Attached Files

•  minicold update.PNG   167.5K   5 downloads
•  miniwarm.PNG   110.96K   5 downloads
•  hot.PNG   110.81K   5 downloads