Help needed: Changed spark plugs now car won't start

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Guys
I need some help please...

I changed the spark plugs this morning, replacing them with identical OEM ones from TPS in Guildford. I connected everything back up and now the car will not start. There is a loud rapid fire clicking noise coming from the coil packs. I could only guess that perhaps the coil packs are not seated properly on the spark plugs causing the spark to spark against the engine casing rather than the plug?

However, I have checked and everything seems to be connected and seated properly - the coil packs certainly won't go down any further. A slightly strange thing that I noted is that the clock inside the car has re-set itself.

I have tried replacing all the old spark plugs in exactly the same cylinder as they came out of but I get the same problem so at the moment I am without a car and kind if need it, certainly for Monday.

I am not technical by any means but I am quite practical and have done my own car and motorbike servicing in the past. This is a simple job, I can't work out what has gone wrong. The coilpacks were newly fitted yesterday but the car worked from the dealer yesterday so assume they cannot be at fault.

Any help will be massively appreciated, I really need to get the car going again!!

Thanks
Martin
 
1) How much did you tighten the plugs when you reinstalled the new ones (hopefully finger tight + 1/2 a turn at most)?
2) Did you ensure the plugs had the little metal screw caps on the top (sometimes these aren't screwed on and are loose in the box)?
3) If you put a straight edge over the coil packs does it sit level (e.g. they are all correctly inserted to the right depth)?
4) Did you push the coil pack loom back on until you heard the clips 'snap'?
5) Have you reconnected any other clips / electrical connections you may have undone to get to the plugs (maybe MAF)?
6) Check all the fuses by he battery, and if they are all OK, prize the driver side of the dashboard end cap of (you have to open the door to get to it) to see if all the fuses in there are OK - use your handbook to check fuses.
7) Did you disconnect your battery to do the job?


I'm worried your clock has reset - that doesn't sound normal. hope it hasn't caused ECU issues. Never heard of clock resetting as part of plug change. Is battery OK.

Very strange.
 
most odd, is there enough wiring (cant pic off hand) to pull out a coilpack & fit a plug, earth it off the cylinder head & check for a spark? Perhaps there has been a spike or power cut that has confused a module, you could also try putting everything back together & disconnecting the battery for 30 mins assuming you dont have a diagnostic lead like VCDS?
 
Thanks for the quick response Guys... Glad you also think this is strange - I've changed a lot of spark plugs before and never had this!

To answer Warren's questions first of all - questions 1-5, all yes. Q6, I don't know where my handbook is so can't easily check the fuses. And finally no, I didn't disconnect the battery, maybe I should have?

Khufu - the isn't the space that I can see to do what you suggest. Unfortunately I do not have VCDS.

I'll put everything back together, using the new plugs (since the issue is still there with the old ones), disconnect the battery and leave it for a while. I have to go out soon so will leave the car overnight then connect everything back up tomorrow. Nightmare, there was me thinking it''d be a quick hour's work and now I've wasted ****** hours and still have a busted car!
 
Did you replace each plug one at a time, or did you remove the plug leads from all, change all plugs, and then put back?

I suppose you *could* have put the plugs on in the wrong order, resulting in it not starting?
 
I wouldn't thought that's possible, its not like on the old days when you had leads. There are 4 coilpacks with 4 multiplugs that wouldnt stretch you the wrong one.
 
I may be wrong but i believe theres an amplifier that feeds the coil packs! this may be at fault??
 
It looks almost impossible to mess up as the leads connecting to the coil pack are all fixed in place. However, I replaced one plug at a time to make sure I didn't mess anything up. That's why I really can't understand what has gone wrong. For the car not to fire up at all suggests i've done something wrong though! Looks like I'll have to call someone out on Monday morning. ****!
 
You cant cockup the plugs on these cars as the leads are all to length to the assigned hole as such, so thats a non starter excuse the pun, are you sure you havnt knocked or unclipped another connector or left ignition on & shorted something which inturn blown a fuse, you need to get vcds on it to check whats logged tbh, check all fuses, all normal things as tbh not allot you can do wrong doing this job, I did mates S3 other day no issues, no issues & no need to disconnect battery.
 
Got the car fixed this morning and somewhat embarrassingly it turned out to be a completly flat battery. No idea how it lost all its charge in the space of an hour or so but the guy that looked at thinks it probably needs replacing anyway - looks like the original battery so probably is due a change.

I'm very relieved it was nothing major and it doesn't seem to be anything I did - as Nigel said, you really can't **** up a plug change when all the leads are fixed in place. Annoyed I spent so much time taking the new plugs out and refitting the old ones, then refitting the new ones again! Oh well, sometimes it really is the simple things that cause the problems.

On the plus side the misfiring seems to have completley gone with the new plugs.
 
6 yr old battery is tbh, depending on weathering, on its last legs in the eyes of the manufacturers, they state 4-5 years iirc on most batteries.

If its been cuddled inside a garage in winter etc, then will last longer, but yeah its always the simple things lol.

Varta Silver Ultra Dynamic mate, wont look back :)
 
hey, its not impossible to mess up plugs. I had a car in once that drove in fine, changed plugs & then it was like a bag of spanners - found it was one of the plugs tip was bent & touching electrode. Had just plain duff plugs, had plugs snap (Ford Ka & fiesta!!) plugs that are cross threaded in the head (left in & advised customer LOL)

Glad its sorted :)
 
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