I accidently pulled a wire out today whilst I was removing my cat on my Si (zetec) and I don't were it connects to. Its a little blue wire that was near the alternator but I carnt figure where it has come off.

There's a little blue wire that connects to the alternator. Check that your alternator has got a thick wire going to it and a little blue wire, if not then it has come off there. Can't think of any other wires that run near there to hand, only other small wires round there are those running to the fog lights that I can think of

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now im in more of a problem when refitting the wire to the alternator the thread snapped off so now I can't get to fit to the alternator anymore

Has the thread snapped off the alternator or is it the connected nut that has snapped off the wire itsself? If its the thread on the alternator then it looks like its a new alternator job. I managed to pick one up from the local scrappy for £30 wen I needed one so its not that bad, but make sure you specifically get one off a 1.6 si coz the one for the rs1800 etc is wrong (the brackets are a mirror image of what you want!)

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if you have a lil bit of thread left, cut the nut off the wire and use a joining crimp and crimp half to the wire then crimp it down small enough so it will fit onto the threaded stump. it wont be the best repair but it should hold well enough if you crush it down small enough. sames idea as how a lot of oil pressure warning light wires are attached to the oil pressure switch.
(at the back of you engine halfway down if you want to have a look, i believe from memory its that way on a zetec but deff that way on a cvh)

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rs2k powerd escort mk4.....figured id be different!
http://WWW.S2RS.CO.UK

Thanks for your help it was the thread that snapped but there was a just little bit left to fit a smaller bolt I've manage to get it reattached. It took a couple of attempts to get it working as the ignition light kept coming on seems to have stopped now gonna put a voltmeter to test the charging rate tomorrow

Glad to hear you got it sorted without having to change the alternator! Yea, as you say, get a voltmeter on the battery with the engine running to check the charge rate, mine had an intermitant fault where it would charge then stop then charge but it was off more than it was on and after about 70 miles the battery was flat!

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