Electrical Issue - Trying to Start Kills Everything

[Alec Jones]

Last weekend I drove my Clio 182 20 miles no problem, parked up ran a few errands, jumped back in and it started up fine, but whilst turning the car around it seemed like the engine was bogging down and I nearly stalled the car because the revs wouldn't pick up like normal, this problem went away after about 3-4 seconds and everything seemed fine again. Drove it approx 50 miles no issue, at a friends bbq for several hours, get back in no issues driving home so I forgot all about it.

Today I get in turn the key, dash lights up as usual, I wait for most of the lights to go out as usual (a habit from driving diesels) then turn the key to start the car and all electrics seemingly cut out, all dash lights go out and car doesn't respond to turning the key on or off. The car is now completely dead, get out of the car, can't lock it or unlock it etc. Disconnect the battery (which is reading 12.7 V by the way) and reconnect it and its "fine" again. Can lock the car etc. get back in turn the key, the dash lights up.... go to start it and everything cuts again. This is repeatable....

Any ideas guys?

 

[Ads29]

Does the engine attempt to turn over at all when the electrics 'play up'?

 

[Christopher]

Starter connections? Engine earth points?

 

[JamesBryan]

Some sort of earth issue potentially.

Possibly gearbox earth strap broken?

 

[Alec Jones]

Does the engine attempt to turn over at all when the electrics 'play up'?

Nope, there is a click and everything goes dead. It's like it's blowing a fuse, except you can reset it.

I have AA cover that includes the home help option so I'm tempted to give them a call one evening this week and see if they can diagnose it....

 

[Ads29]

I had this with a mates 182 last year, ended up being a heavily corroded earth strap from gearbox to chassis. If you've got some jump leads you can use one as a temp earth from a clean metal source (nothing corroded/ruaty/painted etc etc) to the negative pole on the battery, if it is an earth that's broken this should bypass it and the car should start, obviously I don't recommend this method for anything other than purely diagnosing purposes

 

[bloke]

battery terminals tight? check battery voltage when you turn the key to try and start it.

 

[Alec Jones]

battery terminals tight? check battery voltage when you turn the key to try and start it.

Yeah they're tight. Will give that a try and see what it shows. Presumably you'd expect to see a momentary voltage drop?

 

[Alec Jones]

I had this with a mates 182 last year, ended up being a heavily corroded earth strap from gearbox to chassis. If you've got some jump leads you can use one as a temp earth from a clean metal source (nothing corroded/ruaty/painted etc etc) to the negative pole on the battery, if it is an earth that's broken this should bypass it and the car should start, obviously I don't recommend this method for anything other than purely diagnosing purposes

I'll give this a go as soon as I get a dry evening (currently going through a patch of classic Welsh summertime!). If it fixes it then I'll have to start hunting for the dodgey earth (I'll start with the gearbox one though).

Cheers for the input so far guys.

 

[Alec Jones]

Ok so I took a look at it last night and whilst disconnecting the negative terminal clamp the wire just slipped out! It had worked lose which must have given a poor connection. Tightened it up and it started up straight away.

Great news, however after maybe 30 seconds or so it started to have quite a lumpy idle. When try to increase the revs it struggled / bogged down a bit until it suddenly cleared up, it would happily hold 2-3k rpm but if you let it return to idle it got lumpy again. I took it for a ~ 3 mile drive and it was faultless so I parked it up.

I thought I'd use it to go to work this morning, it started fine but again after about 20 seconds it started getting lumpy again so I just parked it and took my van.

Does this change what you think I should check next? I'm not sure if the poor connection was preventing it starting and this lumpy idle is coincidental and unrelated?

 

[Ads29]

I'd say the issues are unrelated to be honest, I assume there's no warning lights when the engine misfires/goes lumpy?

Probably the most common issues are plugs/ht leads/coilpack related but I would expect these to normally trigger the eml warning.

Could well be a Lambda sensor on its way out, I've seen these leave a car virtually undriveable one minute and then be fine the next, before returning to undriveable again

 

[Alec Jones]

Thread bump to close this out. After using some injector cleaner it was running ok again. It was occasionally lumpy for a few seconds when first started but would then be fine for he rest of the drive. It carried on like this for a few months until it suddenly deteriorated and was very rough. Took it to the garage.... new plugs, leads, coil pack and one new injector later and it’s good as gold again.