Help needed with changing ecu

[coreen]

Hi, I have had loads of problems recently with my mg zs 1.8, 2004. After changing lots of parts I have been advised to change the ECU. I have now got one with the alarm box and one key fob, can anyone advise how to change the ecu and where is the alarm box located?
Thanks

[Zippy Saloon]

If its a MkI then its behind centre console - remove rear part of console (with armrest and leccy window switches), radio, hazard and HRW switches, front half of console and you'll see it at the bottom of the dash support.

This is my MkI in process of getting MkII dash, alarm box is is fixed to bottom of that large metal frame, about 30cm in front of gear lever.
http://i187.photobucket.com/albums/x88/Gary_6315/022-1.jpg

[coreen]

wow that looks quiet hard to do

[Zippy Saloon]

wow that looks quiet hard to do

Getting to the ECU aint too bad.
2 screws and 2 bolts to temove back half of console.
5 screws for front half (forgot that theres one behind / below radio once you get it out)
You can leave gearlever gaitor in place - just unclip it from console (get something under front edge, where rubber mat is), you can twist is sideways to pop it through opening in console as you get it out.

http://i187.photobucket.com/albums/x88/Gary_6315/console-1.jpg

[coreen]

This is really helpful, thank you very much. I have tried to take the ECU out today but it has snap off security bolts on the cage surrounding it at the bottom, do you know how I can get these off?

[Zippy Saloon]

I guess the head of the bolt would have to be drilled or ground off but not sure about access to them off hand.
Will have a look at mine in AM and see what I think, can't get to it at the moment

[coreen]

Thats fantastic and once again thanks for all your help.

[Zippy Saloon]

Just had a look at mine and it would be dead easy, yours being slightly later has the security shield I guess ("g" below)

http://i187.photobucket.com/albums/x88/Gary_6315/ecu.jpg

If you can get a hacksaw blade on the head you may be able to cut a slot like a screw head and simply undo with a screw driver, failing that cut a slot and use hammer and old screwdriver like a chisel to try and tap it undone.
Theres a very slim chance that a couple of taps on the head of screws with hammer will loosen them - rare it works but could be worth a try.
If above fails your looking at drilling or grinding heads off - drill could be unlikely due to access but something like a dremel with a grindstone in it or even a little grindstone in a drill, something like this (wear goggles though!)

http://i187.photobucket.com/albums/x88/Gary_6315/Stone_Burr.jpg

Whereabouts are you - someone may be able to give a hand.

To just change over ecu for now I guess you could cut the security shield as below and just cable tie / tape new ecu to old one for now, gives you a chance to get stuff together to do proper job.
http://i187.photobucket.com/albums/x88/Gary_6315/ecu2.jpg

[coreen]

I have changed the ecu and alarm box but I wouldn't have been able to do it without all of your help and the pictures you sent so a massive thank you. I am just going to take the car for a test drive so fingers crossed.
Once again many thanks

[Zippy Saloon]

Good luck - hope its cured, what was it doing anyway?

[coreen]

just got back everything seems fine again, thanks guys massive help i will be on here more often now

[coreen]

I take it back the problem isn't cured. The car wouldn't start about 8 weeks ago, 3 mechanics later they decided it was a fuel pump problem so we had this changed. The car would then start but the main fan was constantly running and the revs were sitting at 2000 at least and it had a huge judder/missfire problem. It was plugged into a code reader and we were told it needed an IACV and a purge valve, these were changed and the car as not much better so it was plugged back into a code reader and came up with temp sensors, these were changed but it made no difference. Another kind soul on here advised it could be the ecu which has just been changed and the car ran fine last night but went to use it this morning and its back to revving at 2000 to 3000 when idle and the juddering/missing is worse. Any ideas as none of the 3 mechanics know where to go next. One of them has said there could be a crack in the injection manifold - could this cause these problems?

[coreen]

http://www.themgzs.co.uk/vb/attachment.php?attachmentid=3639&stc=1&d=1335126594

hi guys
quick update on my mg zs , i think we have found the problem

[Jono-MG]

http://www.themgzs.co.uk/vb/attachment.php?attachmentid=3639&stc=1&d=1335126594

hi guys
quick update on my mg zs , i think we have found the problem

What on earth (excuse the pun ;)) is/was that rats nest meant to be?

[coreen]

that is the loom coming from the right side of the ecu , 5/6 wires fused together plus 4 bare cables under the throttle body

[Ritchy]

quite common for them to go there where they wear on the ecu bracket, does all sorts of things, holds injectors on ect