Weak spark

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lenny
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Just wanted to know if i am getting a weak spark to the dizy cap and i know the coil is good. Could it be the amp ? :?

(480. 280ge)

thank you.

Pistonhead
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Re: Weak spark

I do not know Lenny, is it a weak spark you have?

Please be more specific, what is it that your asking for help on?

Car will not start, engine will not turn?

So, do elaborate on what your issue is?

Cheers,

lenny
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Re: Weak spark

On sunday i set of from home and got about three miles from home and she died, i tryed to re start it but all it would do was turn over. The aa turned up and said it had a week spark becaues the coil was no good. I got the coil checked and its fine.
So she is now at home and will turn over but will not start. :cry:

Pistonhead
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Re: Weak spark

Hmmmm,

Assuming there is plenty of fuel, let us take from what the AA Man says, given a weak spark and coil being o.k. I would turn attentions to the ballast resistor if fitted, check the resistance of the ballast resistor, I will need to look up the values for you and get back to you on this.

Check the resistance of the high tension lead form the coil to the dizzy. Again, value to follow. Forgot the most basic, hoping th AA man should have checked this as his basic check, the battery, get it fully charged up whilst you are diagnosing this fault. Does the engine turn at a resonable rate or is it sluggish?

Accepted the spark at the dizzy is weak, check to see if it reaches the spark plugs, then check the dizzyits self and rotar arm.

Check the resistance at the TDC centre lead, values to follow.

Finally, you want to look at the ignition module, generally these are good but can fail, can you borrow one as a substitute? They are expensive though some specialist companies can refurbish these for you, they say it can be tested but, I do not trust any company to own up to claim your module was fine given they can charge a whole lot more claiming it has been refurbished.

Note the ignition module needs good earthing, check the body work surrounding the module, if corroded and swollen, try and attach an earth lead to it and to some sound metal work.

Will send you the values asap.

Cheers,

PS, hope you have not got any immoblisers fitted, if so, eleminate this from the equation before checking any of the above.

lenny
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Re: Weak spark

It dose have fuel . there is no immobliser.

The roter arm dose spin but no spark is getting to the plugs, but the spark is getting to the dizzy (witch look ok no cracks ). :?

lenny
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Re: Weak spark

Sorry fogot to ask where would i find the ballast resistor? Or find out if it has one.

Pistonhead
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Re: Weak spark

I think it sits n/s inner wing or nearer the ignition coil. (Effectively, trace wires from the ign. coil backwards and you should stummble up on it, if fitted).

The unit is made up of two creamic fuse looking thingys" joined together as one unit. As far as connections are concerned, there is one connector at the bottom and one each at the top from each tower. The bottom one is shared between the two towers.

The towers, I think have a coiled wire attached in it some how. Take care these do get very hot. The two towers should be easily identifyable, they are white, have a coiled wire to it and stand approximately 2" tall side by side as one unit.

If you do not find this, do not panic, like I mentioned earlier, only the earlier model had them but I do not know of the cut off points.

As I have some value to give you, I will follow this through, now with thw holidays, I am off till Tuesday, so I have no access to a computer hence website till then, I am expected in over the holidays for a short period, so if I can, I will update you.

Cheers,

Pistonhead
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Joined: 17.12.2006
Location: Loughborough
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Re: Weak spark

I think it sits n/s inner wing or nearer the ignition coil. (Effectively, trace wires from the ign. coil backwards and you should stummble up on it, if fitted).

The unit is made up of two creamic fuse looking thingys" joined together as one unit. As far as connections are concerned, there is one connector at the bottom and one each at the top from each tower. The bottom one is shared between the two towers.

The towers, I think have a coiled wire attached in it some how. Take care these do get very hot. The two towers should be easily identifyable, they are white, have a coiled wire to it and stand approximately 2" tall side by side as one unit.

If you do not find this, do not panic, like I mentioned earlier, only the earlier model had them but I do not know of the cut off points.

As I have some value to give you, I will follow this through, now with thw holidays, I am off till Tuesday, so I have no access to a computer hence website till then, I am expected in over the holidays for a short period, so if I can, I will update you.

Cheers,

lenny
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Joined: 09.10.2007
Location: West Sussex
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Re: Weak spark

Thank you for help Rakesh i have now got a spark but the fuel pump is not working but i am on the case slowly..!! :idea: