13 replies to this topic

[andycleeds]

Hi

I have a 1994 cooper with injection probs. Thinking of buying a used ECU to see if will cure my running fault as suspect my existing unit is faulty. If I do can I just plus this onto my car and it will run as normal straight away OR do I have to buy an unprogramed ECU i.e a brand new one?

Hope someone can help

thanks

[Sprocket]

What makes you think its the ECU?

[andycleeds]

What makes you think its the ECU?

Hi,

Stepper motor not working properly, erratic function. Car been set to compensate, so when stepper decides to work, which is after about 30mins of driving the car revs at 5000rpm. I switch off car to reset and drive as normal with idle just under 1000 rpm until the next time the stepper decides to work.

Car has been in a garage, all wiring checked and relays replaced where faults found. The garage suspects stepper and I tend to agree as I can't feel or see it working.

Read some posts on this forum from a chap in the USA who had the same problems, he replaced the ECU and the car was fine.

A new throttle body including stepper retails in the UK at £360, which I can get from rover brand new. However seen a 2nd hand ECU for sale, so thought I get that first to see if it solves my running faults.

My car has also developed electrical faults too, horn, lights, rear screen, indicators, fan, radio all have stopped working. Fuses OK. Its causing me a real headache, I'm having to drive a mates ford orion but want my mini back on the road.

Can you help? If I replaced ECU can I just plug and play or do I need it reprogrammed?

Thanks for answering my post.

Andrew

[andycleeds]

Hello

Anyone know the answer, sproket you replied but did not follow up. any ideas.

Thanks

[Saxo-Fiesta-Mini]

get it attach to diagnostics if u cant then u shud be able to get a 2nd hand one but make sure the ecu doesnt have incopirated imoblilser as if it does then ull need the key, coding ring and ecu to match then will work could also be the lamba probe as this will adjust the fueling depeding on reading / temp

[minimat]

Try another stepper motor i had a faulty one that seemed partially seized up.These are not available from rover on their own so pop down the local scrappy and get one off a rover 200/400 or metro, these are located in the air intake,different position to your mini but the same motor.

[rozzer1275]

if the ecu is programed to the factory immobliser this can be disabled by cutting on of the wires on the ecu multi plug, can't remember which one but could find out if needed.

[andycleeds]

Thanks for the replies.

I have now cleaned all the throttle body and stepper etc. I have put back on car and connect the 2nd hand ECU, the car did not start. Now put the original ECU back on and the car started first time. The stepper appears to work but is still temperamental. Might do as suggested and get a 2nd hand rover 200/400 stepper motor and see how I get on with that. If that does not cure the fault then its the ECU and I'll send off for reprogramming


Re the ALARM my key fob LED lights up but the alarm does not work. Is the alarm run by the ECU and if so where are the sensors in the car that the key fob would send a message to, to activate the alarm?

Thanks

Andrew

[bamby]

Thanks for the replies.

I have now cleaned all the throttle body and stepper etc. I have put back on car and connect the 2nd hand ECU, the car did not start. Now put the original ECU back on and the car started first time. The stepper appears to work but is still temperamental. Might do as suggested and get a 2nd hand rover 200/400 stepper motor and see how I get on with that. If that does not cure the fault then its the ECU and I'll send off for reprogramming


Re the ALARM my key fob LED lights up but the alarm does not work. Is the alarm run by the ECU and if so where are the sensors in the car that the key fob would send a message to, to activate the alarm?

Thanks

Andrew

the alarm and immobilisor are managed by the ecu, you will need to re connect your fobs to the car by folowing the re sync process set out in the handbook for the car. when the system is removed it usually resets so the fobs will need re adding to the car..

[minimat]

Which alarm do you have? if the remote only has one button (lucas 3as system) then the alarm and the ecu are not programed together and are interchangable,the sensor for this is a wire plugged into the alarm ecu which is mounted in the centre of the dash, if the remote has two buttons (5as system) then the ecu and alarm are matched together and would need re progaming to work if one part is changed.

[andycleeds]

Thanks. My key fob has one button, so if I have a look at the centre of the dash to find the alarm ECU do you know what the likely fault is, as my LED lights up but alarm is not working.

Thanks for all the replies.

Andrew

[minimat]

Try pressing the button several times near the car to re sync the fob,make sure the batteries are good in the fob though and hold the fob next to the alarm unit as they work on infa red and the range is not very good!
The alarm is activated by the door, bonnet,boot switchs so if any of these are dirty or sticking it will not work properly.
These alarms are very poor so if you manage to turn it off it is best left off!

[andycleeds]

Right thanks. Maybe I'll leave it alone then and not fix it. If the alarm not working has no effect on the car's running then I may just leave well alone.

Andrew

[minimat]

All the alarm,imobiliser unit does on this early system is cut the power from the ignition switch to the main starter relay in the black box on the servo nothing more,i used to think it cuts the fuel pump as well until mine went wrong and i had it removed.
A faulty alarm unit should in theory have no effect whatsoever on the cars running,it will either start or it won't.