Hi, before I go into things I would like to say that I came across the forum looking for answers and have read people with similar issues but have not found an workable solution.
The tale begins!
One day I go to start my newly purchased second hand Stilo and I get a message display on screen, 'Security warning, loose connection' and this gives a knocking/ticking sound from the fuse box area and the engine wont start. This would only happen if the car had recently been driven but not occur right away (it would have to be left for a couple of minutes). I would sit in the car with the key turned until the message cleared itself and let me drive off. My partnets father is a MG mechanic so knows a good few things.
The plot thickens!
As time progressed and we could not solve the problem and just lived with it (annoyingly) yet another symptom appeared. While accelerating in gear 2 at about 4000rmp the engine cut all power but stayed running, the accelerator hardly responded it would increase the revs from about 1100-1300rpmwhen being pressed. When it cuts I get 'Engine Fault' display on screen, usually the engine idles at 700-800rpm once warmed up but in this state 1100+. When this does occur I am usually ok to stop the engine, start back up and drive off but often it would occur right away again. At this point I was not getting both faults at the same time. I was eventually forced to change back to my old car when the problems became more and more frequent and took longer for them to clear/fix theselves. It became so that the errors where occuring every drive and both at the same time.
We left the car parked up for a couple weeks and the battery completely drained itself, no obvious signs of anything staying on and leaking it. So we charged it back up but still had the problems.
Things we have checked/discovered over time:
Firstly things I was reading about the loose connection problem was pointing towards the D4 connector, wasnt wure if we had the right one at first but it was under the fuse box and was big and chunky, cleaned this up etc etc, no improvement. We checked some of the small fuses and found a burnt and corroded fuse which if I remember was for climate control. This is now replaced.
We have run a fault code reader on the car which brings up the same 3-4 codes each time that dont seem relevent at all and only display when I have engine fault up.
Codes:
1600 - Serial communication link malfunction
1601 - Internal control module memory check sum error
1602 - Control module programming error
1702 - Transmission Control System Electrical
If I have had the engine fault problem occur and I start the engine often it works fine but then out of gear I rev high and it cuts again.
Very recently we have discovered that if we apply preasure on the left connector going into the ECU the clicking stops and you can hear the plug 'engage', the error clears. This is the closest we have achually come to improving anything! We removed the plugs covers, checked for any obvious breakages and freed the wires up a but by giving it more room and taking off cable tie etc. All the pins look fine, no burns or discoloration or any moisture to be seem. The only thing we did notice was the ecu and connectors got extremely hot when the engine had been running and it only gets the fault when its running and more so when being revd high/driven faster but we are still unsure if this will be making the problems occur or just a bad design having it on the engine block.
Once we discovered the plug problem we decided to buy some contact cleaner from Maplin electrical store, prayed it alllllll over both sockets/plugs on the ECU and dabbed dry with tissue and left to dry. Now im using the car again but the problems are again getting more frequent and applying preasure doesn't work, we have to take the plug off and on a good few times sometimes and that doesn't even work by the time it does its probably just working because its been left for a good 5-10 mins of being stuck. Even if I do get driving I am still driving round with engine fault on screen but sometimes replugging the connectors in clears it.
Summary:
'Security warning, loose connection' (when engine is warm/used)
'Engine Fault' (While driving typically at high revs but not always)
Just to note the main issue is the engine fault and cutting engine which then brings on the clicking loose connection fault.
Diagnostics point toward ECU connection or faulty ECU itself.
The tale begins!
One day I go to start my newly purchased second hand Stilo and I get a message display on screen, 'Security warning, loose connection' and this gives a knocking/ticking sound from the fuse box area and the engine wont start. This would only happen if the car had recently been driven but not occur right away (it would have to be left for a couple of minutes). I would sit in the car with the key turned until the message cleared itself and let me drive off. My partnets father is a MG mechanic so knows a good few things.
The plot thickens!
As time progressed and we could not solve the problem and just lived with it (annoyingly) yet another symptom appeared. While accelerating in gear 2 at about 4000rmp the engine cut all power but stayed running, the accelerator hardly responded it would increase the revs from about 1100-1300rpmwhen being pressed. When it cuts I get 'Engine Fault' display on screen, usually the engine idles at 700-800rpm once warmed up but in this state 1100+. When this does occur I am usually ok to stop the engine, start back up and drive off but often it would occur right away again. At this point I was not getting both faults at the same time. I was eventually forced to change back to my old car when the problems became more and more frequent and took longer for them to clear/fix theselves. It became so that the errors where occuring every drive and both at the same time.
We left the car parked up for a couple weeks and the battery completely drained itself, no obvious signs of anything staying on and leaking it. So we charged it back up but still had the problems.
Things we have checked/discovered over time:
Firstly things I was reading about the loose connection problem was pointing towards the D4 connector, wasnt wure if we had the right one at first but it was under the fuse box and was big and chunky, cleaned this up etc etc, no improvement. We checked some of the small fuses and found a burnt and corroded fuse which if I remember was for climate control. This is now replaced.
We have run a fault code reader on the car which brings up the same 3-4 codes each time that dont seem relevent at all and only display when I have engine fault up.
Codes:
1600 - Serial communication link malfunction
1601 - Internal control module memory check sum error
1602 - Control module programming error
1702 - Transmission Control System Electrical
If I have had the engine fault problem occur and I start the engine often it works fine but then out of gear I rev high and it cuts again.
Very recently we have discovered that if we apply preasure on the left connector going into the ECU the clicking stops and you can hear the plug 'engage', the error clears. This is the closest we have achually come to improving anything! We removed the plugs covers, checked for any obvious breakages and freed the wires up a but by giving it more room and taking off cable tie etc. All the pins look fine, no burns or discoloration or any moisture to be seem. The only thing we did notice was the ecu and connectors got extremely hot when the engine had been running and it only gets the fault when its running and more so when being revd high/driven faster but we are still unsure if this will be making the problems occur or just a bad design having it on the engine block.
Once we discovered the plug problem we decided to buy some contact cleaner from Maplin electrical store, prayed it alllllll over both sockets/plugs on the ECU and dabbed dry with tissue and left to dry. Now im using the car again but the problems are again getting more frequent and applying preasure doesn't work, we have to take the plug off and on a good few times sometimes and that doesn't even work by the time it does its probably just working because its been left for a good 5-10 mins of being stuck. Even if I do get driving I am still driving round with engine fault on screen but sometimes replugging the connectors in clears it.
Summary:
'Security warning, loose connection' (when engine is warm/used)
'Engine Fault' (While driving typically at high revs but not always)
Just to note the main issue is the engine fault and cutting engine which then brings on the clicking loose connection fault.
Diagnostics point toward ECU connection or faulty ECU itself.
