GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: bobbito on 27 February 2010, 18:47
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Hi all, can anyone help me here. Just finished replacing the head gasket/timing belt/oil+filter/fuel filter. Timed her up but won't start?
When I turn on the ignition there is a single spark but no spark at all when you turn the engine over. RAC man came out and said its the Hall sender on the side of the dizzy and recommends replacing the whole dizzy. Only other thing I have done is electrical tape round a wire which comes from the starter motor and goes behind the oil filter, as wire was showing. I think it is the knock sensor but not sure.
Any ideas?
Thanks guys
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i dont think the hall sender would do that? if the dizzy were completely fubared maybe, but disconnecting the hall sender doesnt stop it from sparking, just switches fuelling to batch injection as opposed to sequential as ecu cant tell when TDC occurs.
id be more inclined to look at coil before dizzy.
knock sensor could well stop it from starting. so maybe start there?
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I've replaced the coil and had it checked already. It's really odd I can't work it out.
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Immob. kicking in
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If it was the immob would it not start then stop seconds later much like starting the car with an un-chipped key?
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can you get it scanned for codes?
are you getting a constant spark from the king lead to the dizzy cap centre? If so, It could be something stupid like the dizzy cap centre contact broken or jammed in (its carbon and brittle) or the rotor arm is open circuit (less likely)
or if not, then a wire broken or plug off / dirty to the dizzy, the crank / cam sensor or the coil.
Check with a lamp or meter whether there is a regular 12v pulse to the coil (well more like 10 to 11v under cranking) and take it from there, if the coil is sparking constantly then look at the inside of the dizzy, the king lead from the coil and the diz cap.
If not, check sensor and coil wiring.
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Coil / imo / ignition switch.
These are all things that i have experienced causing this.
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I'm going to replace the dizzy and hall sender (which is on the side of it I think), when it arrives. If that doesn't work I'll try and get it on a vagcom. It's so annoying especially after doing some much work with replacing head gasket, getting the head skimmed, new timing belt and tension pulley, oil change and all filters. Now I have to drive a bloody Rover until the golf is fixed. Oh the shame!!!
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This is exactly what happened when the hall sender went on my mk2. As soon as the ignition is turned on there is one spark, after that there's nothing. Have a play around with the hall sender connections before you replace anything
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Just went and had a good fiddle with the hall sender and leads + some WD and cleaned battery terminals and connecting wires but still no dice. Dizzy is in the post so will soon find out if the RAC man was right.
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Fitted new dizzy under RAC mans recomendation but still no start and one spark from king. Just double checked cables and the engine speed sensor behind oil filter looks shagged with bear wires and corrosion. Removed the cable and sensor but bolt sheared so quite a bit if bolt left behind. My new questions are;
1) If the engine speed sensor was knackered would it stop the car from starting
2) does the sensor undergo alot of pressure as I can't be arse to remove front of car and radiator to drill out a sheared bolt shaft.
Cheers guys.
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1. definately, thats what the timing signal is derived from
2. the bolt needs to come out, or you wont get it fixed at all mate. the sensor is critical and probably bolted to 25nm but thats irrelevent now the head has snapped off. And easy way to remove a snapped bolt (if you have the room) is to drill a hole down the centre of it, and bang in an allen key of the same size as the drill, pick something about 1/3 of teh size of the bolt, when the allen is hammered deep into the hole, it gets a great bite, and is hard as a whores heart, it will not bend or flinch and the bolt will screw out.
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Legend Flyspeck. Now all I need to do is find an engine speed sensor by the weekend. GSF? Eurocar parts?Dealer??££?
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yeah dizzy deffo wont cause this on an AGG. AGG/ADY/ABF engines will still run with dizzy plug completly disconnected! if it was the immob the car would fire up for a few seconds then cut out, so not that either.
so yeah, id say crank sensor, or possibly coil. the wiring to the crank sensor is all knackered so even if it was working I'd still replace it, since its only a matter of time before it fails completely.
GSF sell em for about £50, so get on the phone to your local outlet ;)
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Part bought this morning from gsf for 40 odd quid on next day delivery so will be taking the front of the car off over the weekend to remove the left over sheared bolt from the block. Coil is only a year or so old and voltage from it reads ok so I live in hope.
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good one bud, gsf are the daddies lol
let us know how you get on!
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Yay. After removing front and fitting new crank sensor the car finally starts. Only thing now though is sorting out the dizzy as I had to remove it and now it runs quite lumpy. Do I have to plug it into a VAGCOM to sort it out.
Also the new timing belt is on but seems to wine a little almost like a super charger mine. I checked the belt tension by twisting until belt wont twist more than 90 degrees. Is this correct.
Cheers for all your help guys.
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sounds like the belt is too tight, I would say yeah 90o plus a wee bit, another 10 - 20 but it might bed in.
If the dizzy is in the correct place it would just sort itself out mate, must be a tooth out maybe?
Sounds like its a tiny bit wrong, maybe slightly retarded, is the hot tickover high? If so, it could be the other way a tooth, but usually lumpy idle is late timing if its that at all.
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line the top & bottom end to tdc, then turn the dizzy till the rotor armn lines up with the notch on the dizzy housing. thats all you need to do on crank sensor equipped cars :) you might find the dizzy is locked in place, if so you have to loosen the belt off and move dizzy round that way. as above, 90degree twist is right for the 8v, if its whining maybe the tensioner has had it
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All sorted now. Lined up intermediate pulley again and rotor. Also slackened the timing belt. Runs like a dream now. Thanks for all you help guys you've saved me a fortune. Way more useful for technical issues than ed38.
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nice one bud ;)