52 plate 1.1 rough running

1st October 2014, 19:45

Hi all, my cousin has a saxo mentioned above. Anyway she took it to a garage today to have her drivers door lock changed as she couldn't open it. The garage didn't drive it anywhere but apparently had to weld something in the drivers door. On the way home the cars engine management light has come on, the Rev counter has stopped working and it's running rough and to me it sounds like it's running on 3 cylinders. My first thought is spark plugs or Coul pack. Any idea if the welding could of affected this and why rev counter wouldn't be working before she buys a new coil pack and starts throwing money at it? Im going up Saturday to put in some new spark plugs before we get a new coil pack to see if that's a possible fix. Any help appreciated. Cheers

1st October 2014, 20:01

Depends where the welding was done, there's a loom going through the inner edge of the door towards the front wings, when I was having my top hinge welded we had to watch all the wires there, any falling sparks burning wires, heat passing through the whole area damaging wires etc. A good garage would of known they have to fire watch but you will get the odd garage that won't do it, not saying that's the case here but will be worth checking the wiring in the drivers area.

1st October 2014, 20:06

I don't think anything in the door could cause running lumpy because I think it's only locking and speaker wire but do you thinking could have shorted something by getting those wires hot?

1st October 2014, 20:13

The wires are copper so good heat conductors so it's a possibility although a small one if the welding was done towards the outside edge of the door away from the A pillar, the inner edge would of been more risk due to sparking as well as heat. Have to keep in mind that all the loom meets at the drivers side to feed the dash lights, dials etc so could be worth checking the wires otherwise have a look under the bonnet to see if anything is noticeable that has been tampered with to cause the engine management light to come on (I have actually seen garages tamper with cars to cause the customer to return)

1st October 2014, 20:21

I know he messed with the drivers lock and also the hinge because it creaked so he said to her I've also sorted the creak out but now the door doesn't stay open unless being held and the lock has broken again. Not going back there but il have a look at the door wiring before we go fitting new plugs etc. I checked all the coil pack and plugs under the bonnet and they all were on tight.

1st October 2014, 20:29

Hopefully someone else on here will be able to give you a few more pointers to check just incase it's still playing up after checking and replacing things, I know there's a few odd sensors that can be disconnected and the engine will still run but eventually the engine management will give the warning light.