Lancia Beta Forum

Technical stuff => Ignition => Topic started by: speedyK on October 14, 2013, 10:51:20 PM



Title: Is coil failure the answer?
Post by: speedyK on October 14, 2013, 10:51:20 PM
The last time I drove my Beta Spyder was about 4 months of months ago, when it ran without problems.

When I wanted to start it recently (with battery jump leads connected to another car which was supplying a healthy charge), it turned over happily but would not fire at all.

I replaced the plugs. Still nothing  :-\

I thought maybe the small amount of very old petrol in the tank was the problem, so added 10 litres of fresh 98 RON, disconnected the fuel feed and pumped it through until about 300 ml was collected into a bottle. This did at least show that the fuel pump is working.

Connected it up and tried again. Nothing  :(

Checked the spark at the end of the plug lead. Nothing!  :o

Checked the spark coming off the coil to distributor lead. Nothing.  :o :o

Does this mean that my coil has failed? Any other possible explanations?  ???


Title: Re: Is coil failure the answer?
Post by: Neil-yaj396 on October 15, 2013, 06:34:13 AM
Points failure (if an early car), or the electronic ignition pack has failed? If you can borrow a coil a quick swap will rule that in/out.


Title: Re: Is coil failure the answer?
Post by: lukasdeopalenica on October 15, 2013, 08:12:43 AM
Check if there is voltage at primary coil terminals when ignition switch is in ON position


Title: Re: Is coil failure the answer?
Post by: speedyK on October 19, 2013, 05:37:10 PM
It's a 1981 (electronic ignition) car. There is a spark at the coil terminals and having looked more carefully, there IS a spark at the end of the coil to dizzie lead, but that doesn't necessarily mean that it is working properly, does it.

Not really feasible for me to borrow a coil. Can anyone tell me what the exact spec of the Bosch coil on a 1981 Spider 2000 is?


Title: Re: Is coil failure the answer?
Post by: Thotos on October 19, 2013, 08:46:16 PM
Bosch electronic ignition on Betas (on my Trevi at least but I suspect all betas are the same?) is a bit strange in that it uses a 9V coil with ballast resistor but there's no ballast bypass when cranking the engine. Try bypassing the ballast resistor. It's easy, simply take the 12V feed from one end of the ballast and connect the 12V straight to the coil. They are all spade terminals so no tools needed. You need the wire off the ballast that doesn't already go to the coil 12V terminal. In the case of my Trevi that's the wire on the ballast nearest the inner wing. I've been running the Trevi like that for a while now and haven't burned the coil but then again my 12V feed only has 10V on it with the engine running.


Title: Re: Is coil failure the answer?
Post by: speedyK on October 20, 2013, 12:09:56 AM
Try bypassing the ballast resistor. It's easy, simply take the 12V feed from one end of the ballast and connect the 12V straight to the coil.
Just checking before I do anything: you're saying take red lead no.1 coming out of the loom and connect it directly where red lead no. 2 attaches to the coil terminal, yes?
(http://img36.imageshack.us/img36/9632/fnlj.JPG)


Title: Re: Is coil failure the answer?
Post by: Thotos on October 20, 2013, 12:29:23 AM
Yes, that's what I'm saying. Just to be sure, check that lead number 2 on the coil at the moment goes to the other side (non-1) of the ballast resistor. If you have a voltmeter it's worth checking how many volts you have at wire 1.


Title: Re: Is coil failure the answer?
Post by: speedyK on October 20, 2013, 04:22:49 PM
Yes, that lead no. 2 loops round from the ballast resistor at the top of the pic.

I'm just a bit concerned about what peteracs said in another thread:

"I suspect that the ballast resistor may have been left in

a) To keep with the same part, though why there is no bypass is maybe just a price cutting exercise when batteries improved and with electronic ignition.

b) If the coil shorts then you have some safeguard against the wires burning out and potentially causing a fire under the bonnet. Also it limits the current drawn when you connect/disconnect the coil which is done via the elec ignition, presumably a transistor in it."


I wouldn't like to see it go up in flames!  :o


Title: Re: Is coil failure the answer?
Post by: Thotos on October 20, 2013, 06:37:51 PM
I certainly wouldn't want to try to convince you to do something you don't want to do. But bypassing ballast resistors during engine cranking is very common practice and it's what all ballast ignition systems that I have seen do except on the Beta  :-\  The same Bosch electronic ignition system is fitted to the Gamma and that bypasses the ballast resistor during engine cranking. I am not suggesting that you run your car with the ballast bypassed permanently (although that's what I've done with the Trevi and it hasn't gone up in flames yet - I'll fit a bypass relay one day...). I'm only suggesting bypassing the ballast resistor to see if you get a spark and the engine starts. You need a certain amount of voltage to get a spark to jump a gap (about 20,000 volts) so if your 9V coil only gets about 7 volts while the starter motor is drawing lot's of amps from the jump leads, you may have 'only' 15,000 Volts out of the coil and it may just not be enough to produce a nice strong spark.


Title: Re: Is coil failure the answer?
Post by: Neil-yaj396 on October 20, 2013, 07:33:58 PM
.....there IS a spark at the end of the coil to dizzie lead, but that doesn't necessarily mean that it is working properly, does it.


The presence of a spark here seems to indicate that the coil is working. As Theo suggests it's probably the strength of the spark that is the problem.


Title: Re: Is coil failure the answer?
Post by: speedyK on October 20, 2013, 08:15:59 PM
I certainly wouldn't want to try to convince you to do something you don't want to do. (...) I'm only suggesting bypassing the ballast resistor to see if you get a spark and the engine starts.
it's not that I don't want to do it, it's more that I want to understand what this will tell me.
If it starts by bypassing the ballast resistor, does that mean that the ballast resistor is defective and needs replacing and the coil is actually OK?

I'm not the greatest expert on electrics, so want to tread carefully  :)


Title: Re: Is coil failure the answer?
Post by: MattNoVAT on October 20, 2013, 08:34:35 PM
it's not that I don't want to do it, it's more that I want to understand what this will tell me.
If it starts by bypassing the ballast resistor, does that mean that the ballast resistor is defective and needs replacing and the coil is actually OK?

I'm not the greatest expert on electrics, so want to tread carefully  :)

A highly commendable approach!


Sent from my iPhone using Tapatalk - now Free (http://tapatalk.com/m?id=1)


Title: Re: Is coil failure the answer?
Post by: Thotos on October 20, 2013, 10:43:29 PM
If it starts by bypassing the ballast resistor, does that mean that the ballast resistor is defective and needs replacing and the coil is actually OK?

Most likely it'll mean that there's nothing wrong. If the car starts by bypassing the ballast resistor, then put everything back to normal, fully charge the battery and the car will start again.

You said you were trying to start the car with jump leads from another car. The starter motors on these twincams can be up to 1.6KW which would require over 130Amps. Depending on the quality and length of your jump leads and the quality of the connection to your car's battery, you may lose a couple of volts so you may only have 10 volts going into the ballast resistor and about 7 volts or less going to your coil.


Title: Re: Is coil failure the answer?
Post by: peteracs on October 20, 2013, 11:06:50 PM
Yes, that lead no. 2 loops round from the ballast resistor at the top of the pic.

I'm just a bit concerned about what peteracs said in another thread:

"I suspect that the ballast resistor may have been left in

a) To keep with the same part, though why there is no bypass is maybe just a price cutting exercise when batteries improved and with electronic ignition.

b) If the coil shorts then you have some safeguard against the wires burning out and potentially causing a fire under the bonnet. Also it limits the current drawn when you connect/disconnect the coil which is done via the elec ignition, presumably a transistor in it."


I wouldn't like to see it go up in flames!  :o

Hi

Completely forgotten about that post......

As a test, I would not worry, shorting out/bypassing the resistor will be fine, just be aware that the coil is not designed to run at 12V or more and will likely fail if you run for more than just a test, the most likely failure would be overheating I guess?

Hope you manage to sort it. I would suggest substituting a known good coil as a failing coil may appear to work without the resistor, but not with and you may just think the resistor is to blame. ideally have one of each to play with of course.

Peter


Title: Re: Is coil failure the answer?
Post by: speedyK on October 21, 2013, 12:07:54 AM
If it starts by bypassing the ballast resistor, does that mean that the ballast resistor is defective and needs replacing and the coil is actually OK?

Most likely it'll mean that there's nothing wrong. If the car starts by bypassing the ballast resistor, then put everything back to normal, fully charge the battery and the car will start again.

You said you were trying to start the car with jump leads from another car. The starter motors on these twincams can be up to 1.6KW which would require over 130Amps. Depending on the quality and length of your jump leads and the quality of the connection to your car's battery, you may lose a couple of volts so you may only have 10 volts going into the ballast resistor and about 7 volts or less going to your coil.

Ah, my mistake, I forgot to add in my first post that I then also replaced the battery with a brand new one which was fully charged - and I added a booster battery pack. All to no avail.


Title: Re: Is coil failure the answer?
Post by: speedyK on October 21, 2013, 12:10:31 AM
I would suggest substituting a known good coil as a failing coil may appear to work without the resistor, but not with and you may just think the resistor is to blame. ideally have one of each to play with of course.

Peter
If you had to make a choice, would your money be on the coil as the source of problems, or the ballast resistor? I'm guessing the coil...


Title: Re: Is coil failure the answer?
Post by: lbcoupe76 on October 21, 2013, 12:18:06 AM
When you are trying to turn it over does the coil get hot?, does the ballast resistor get hot?. And i do mean hot.


Title: Re: Is coil failure the answer?
Post by: Thotos on October 21, 2013, 02:51:44 AM
If you had to make a choice, would your money be on the coil as the source of problems, or the ballast resistor? I'm guessing the coil...

I would guess neither. If you have no spark then I'd suspect the ignition pickup in the distributor, the wire to the electronic control unit or the electronic control unit itself. If you have a weak spark then I'd suspect the car's wiring and connections causing a low voltage at the ballast resistor and hence low voltage at the coil. If you don't want to bypass the ballast resistor to try and see if the car starts, get a voltmeter and measure the voltage at the ballast resistor and the voltage at the coil + terminal while cranking the engine. You should have 12 volts at the ballast resistor and at least 9 volts at the coil.


Title: Re: Is coil failure the answer?
Post by: speedyK on October 22, 2013, 06:38:09 PM
This is getting complicated  :(


Title: Re: Is coil failure the answer?
Post by: speedyK on October 28, 2013, 07:15:42 PM
I got a multimeter and checked what was happening at the coil:

The voltage measured at the outer poles (the primary winding) = 6.2 volts

The resistance measured from the centre pole (to distributor) to an outer pole = 7.2kohms.

It doesn't mean much to me, but the voltage seems low.

The ends of the ballast resistor get very hot.

Thoughts anyone?



Title: Re: Is coil failure the answer?
Post by: Thotos on October 28, 2013, 08:25:31 PM
I got a multimeter and checked what was happening at the coil:

The voltage measured at the outer poles (the primary winding) = 6.2 volts


Do you mean you measured the voltage across the two poles of the coil? If so, that's wrong. You need to measure the voltage at the +ve terminal of the coil. That's the one that has the wire going onto the ballast resistor. And to be on the safe side and make sure you have a good earth, put the negative probe of your voltmeter on the battery -ve pole and the positive probe of the multimeter on the +ve terminal of the coil. If, as I suspect, you get 7 volts, then bypass the ballast resistor and the car will most probably start. When (and I'm not saying 'if'  ;) ) the car starts, measure the voltage again on the coil +ve terminal with the engine running and report back please.



Title: Re: Is coil failure the answer?
Post by: lbcoupe76 on October 28, 2013, 08:53:31 PM
Heat is generated by current, the lower the voltage the higher the current, A failing resistor will lower the voltage as the resistance increase's leading to excess heat across the resistor.


Title: Re: Is coil failure the answer?
Post by: speedyK on October 28, 2013, 09:23:48 PM
put the negative probe of your voltmeter on the battery -ve pole and the positive probe of the multimeter on the +ve terminal of the coil.
Thanks, I was doing it wrong. Measuring as you say, it gives 7.64 volts.

bypass the ballast resistor and the car will most probably start. When (and I'm not saying 'if'  ;) ) the car starts, measure the voltage again on the coil +ve terminal with the engine running and report back please.
With the resistor bypassed, it still won't start. No spark at the end of the coil to distributor lead when held a couple of mm from the engine.


Title: Re: Is coil failure the answer?
Post by: Thotos on October 28, 2013, 11:39:59 PM

With the resistor bypassed, it still won't start. No spark at the end of the coil to distributor lead when held a couple of mm from the engine.


OK, next things to check are:

1. Voltage at the coil +ve terminal with ballast resistor bypassed. Normally this would be 12V but as you only had 7.6V before I'd expect at least 9Volts. That should be enough for the coil. If you have 9 volts or more, make sure you still have them while cranking the engine.

2. Check the earth strap on the engine. Use the meter in resistance measurement between the engine and battery -ve pole. It should be 0 ohms. Assuming that it is, measure it again while cranking the engine. It should stay at 0 ohms.

3. Test the HT lead from the coil to the distributor. Best way to test is swap it with a known to be good one.


Title: Re: Is coil failure the answer?
Post by: speedyK on November 01, 2013, 03:54:05 PM
Thanks for the further tips  :)


I must admit that I'm getting heartily sick of this now   :-\

Been away for a couple of days. Left the new battery on the battery conditioner.

Did the tests as suggested:

With ballast resistor bypassed
Voltage at +ve terminal of coil (other lead to battery -ve pole) = 11.5 V (Don't ask me why!)
When cranking: 10.5 V

With ballast resistor in place (normal)
7.5 V

Resistance check
-ve lead on -ve pole of battery, +ve lead on engine
with ignition OFF = ca. 2.4 Ohms
with ignition ON = ca. 300 Ohms
cranking engine = ca. 600 Ohms

 ???








Title: Re: Is coil failure the answer?
Post by: Per on November 01, 2013, 06:41:37 PM
The voltages are normal. The ign off resistance is normalish, what resistance do you get directly across the voltmeter probes, i.e. touching one with the other?

Resistance with a live circuit cannot be measured with an ohmmeter (but you can wreck the ohmmeter).

Check the voltage between negative pole on the coil and ground with ignition on. You should get either close to 11.5 or close to zero. Try cranking for just long enough to turn the engine a wee bit several times. You should get either of those measurements.

BTW check that all spade connectors are tight. If not pull off and give a gentle squeeze with a pair of pliers.


Title: Re: Is coil failure the answer?
Post by: speedyK on November 02, 2013, 05:24:02 PM
Thanks for keeping at it  :)

what resistance do you get directly across the voltmeter probes, i.e. touching one with the other?
About 0.3 Ohms

Check the voltage between negative pole on the coil and ground with ignition on. You should get either close to 11.5 or close to zero.
I get about 0.02 V


Check the voltage between negative pole on the coil and ground with ignition on. You should get either close to 11.5 or close to zero.
I'm getting 0.02 V

check that all spade connectors are tight. If not pull off and give a gentle squeeze with a pair of pliers.
All tight...





Title: Re: Is coil failure the answer?
Post by: Per on November 02, 2013, 10:18:06 PM
All good news. Except for the condition of the coil that is. But one last check: Measure resistance beween coil housing and engine which should be zero volts. If OK you should have a big fat spark if connecting a plug directly to the coil high voltage lead and just resting the plug on the engine. With the electronic ignition there is normally either a good spark or none at all as far as the electronics are concerned.


Title: Re: Is coil failure the answer?
Post by: speedyK on November 02, 2013, 10:43:15 PM
All good news. Except for the condition of the coil that is.
So, you reckon it is the coil - not the ballast resistor?

one last check: Measure resistance beween coil housing and engine which should be zero volts.
Not getting any reading, so presume that's a zero.

If OK you should have a big fat spark if connecting a plug directly to the coil high voltage lead and just resting the plug on the engine. With the electronic ignition there is normally either a good spark or none at all as far as the electronics are concerned.
I had already tried this last week, holding a plug against the end of the HT lead (connected by using insulated pliers to clamp them together, as the HT lead does not have the part to fit on the plug) and holding the tread of the plug against the engine. Not sure that the connection made between the coil lead and the plug is adequate - but I couldn't see any spark...


Title: Re: Is coil failure the answer?
Post by: Per on November 02, 2013, 11:11:14 PM
Reading between coil housing and engine should be a decisive zero. Most of the coil is painted and in theory high voltage should jump that resistance easily. However if it has been sitting for a while the corrosion between coil housing and engine could have increased significantly. I would loosen the clamp, slide out the coil and sand coil body and inside of clamp lightly. Ditto clamp and engine. Then simply short out the resistor. If still no spark time to try another coil that is known to be good.


Title: Re: Is coil failure the answer?
Post by: speedyK on November 03, 2013, 12:34:06 PM
I can't see that that corrosion could be an issue, as the car worked fine before and was in a dry garage.

Similarly, I can see no reason why the HT lead from the coil could suddenly fail. As a lay person, I could understand a coil suddenly failing more easily.

I don't have any option to borrow a coil, so I suppose I will have to buy a new one to find out.

I would have preferred to be sure that there were no other feasible reasons for a sudden loss of function (the electric control box for the ignition was my other suspect). It would be annoying to pay for a new coil and find no change in the situation.

New questions:
Can anyone recommend a reliable UK supplier for a new coil for a 1981 Beta Spider 2000?
 Is the ballast resistor supplied with the coil?
If I'm ordering anyway and will have to pay postage to Switzerland, I suppose a new coil-dizzie lead and distributor cap plus rotor arm is a sensible idea too while I'm at it.
Any UK supplier stock these items as well as the coil?


Title: Re: Is coil failure the answer?
Post by: peteracs on November 03, 2013, 03:53:27 PM
Hi

Given the coil is not that specific to your installation, do you know anyone who has a spare from another car just to prove the point?

At the end of the day all they do is provide enough HT to cause a spark, so any coil should give you at least proof it is the coil?

I agree, expensive if not sourcing from locally.

Peter


Title: Re: Is coil failure the answer?
Post by: Thotos on November 04, 2013, 01:57:41 AM
Sorry, I haven't been ignoring you but I've been away for a few days with no Internet access.

I would say with some certainty that the ballast resistor is not faulty. You get the right sort of voltage with the ballast connected and you've bypassed the ballast to eliminate the possibility of it being the fault.


Resistance check
-ve lead on -ve pole of battery, +ve lead on engine
with ignition OFF = ca. 2.4 Ohms
with ignition ON = ca. 300 Ohms
cranking engine = ca. 600 Ohms


That's not right!  :-\  You should have zero ohms between the battery negative terminal and the engine at all times. Check the battery negative lead where it bolts to the chassis and make sure the connection is clean and tight. Also check the engine earth strap. I'm not sure where it's located on your car but there must be an earth strap from the engine to the chassis somewhere and it should have clean and tight connections both ends. Per's suggestion of measuring the resistance between the coil body and battery negative terminal is a good one and along the same lines. If the resistance measured there is not zero then you have a bad earth connection either where the battery negative terminal connects to the chassis (which would explain the strange resistance readings between the battery and engine) or where the coil bolts to the chassis. As a test you can connect a jump-lead between the battery negative terminal and the coil's mounting point on the chassis. To test for a spark at the coil, use a spark plug at the end of a spark-plug lead and plug the spark plug lead into the coil. You may have to move the boot back to be able to plug the lead into the coil. But check again your negative connections from battery to chassis, from chassis to engine and from coil body to chassis. You should get zero ohms at all times between any of those points.



Title: Re: Is coil failure the answer?
Post by: speedyK on November 14, 2013, 11:41:26 PM
Tried it again and got 0 ohms. I think I may have accidentally tried the positive pole of the battery last time  ::)

I have ordered a new coil, as I can't find any other explanation.
I hope it arrives soon, as I want to get the Lancia out of my garage and into its usual underground parking space before winter gets hold. We've already had sub-zero temperatures here.
The Lancia is on summer tyres (I do have a set of steel rims with ancient winter tyres that are not fit to drive - I only use them e.g. to be able to move the car when the alloys are away getting new rubber).
(http://img837.imageshack.us/img837/6543/mpab.jpg)



My winter use cars are all on their winter tyres now and my Smart roadster normally has that space.


Title: Re: Is coil failure the answer?
Post by: speedyK on December 14, 2013, 04:46:30 PM
So, after the coil supplier who promised dispatch within three working days finally got the coil to me after nearly 4 weeks, I fitted it.


Not one jot different.

If I disconnect the HT lead from the coil to the distributor and crank the engine, there is on spark whatsoever - until the ignition is turned off and THAT causes the emission of a brief spark.

What the hell is wrong?


Title: Re: Is coil failure the answer?
Post by: speedyK on December 14, 2013, 09:17:59 PM
I'm now wondering if it is the Bosch electronic control unit.

Anyone know if these available anywhere?


Title: Re: Is coil failure the answer?
Post by: Per on December 14, 2013, 11:02:13 PM
What type of trigger does it use for the ignition? If it uses a circular magnet on the distributor shaft triggering a hall element I have experienced the magnet cracking, seemingly when cooling down because it would not start after stopping and attempting restart the nexy day. If it uses a crank sensor (cannot remember when the first instances came) those are a weak spot in many applications. The system would charge the coil ans switching off the coil would fire once as you described.


Title: Re: Is coil failure the answer?
Post by: speedyK on December 15, 2013, 11:10:47 AM
Ah, interesting.
I'll have another look at it.


Title: Re: Is coil failure the answer?
Post by: Thotos on December 15, 2013, 10:24:07 PM
There's no crank sensors on Betas. The problem must be either with the pickup sensor in the distributor or the electronic control unit or, of course, the associated wiring.


Title: Re: Is coil failure the answer?
Post by: lukasdeopalenica on December 16, 2013, 09:50:52 AM
There's no crank sensors on Betas. 
Precising your answer in late i.e. versions with digiplex ignition there is a crank and a cam sensor.


Title: Re: Is coil failure the answer?
Post by: Thotos on December 16, 2013, 10:07:01 AM
Precising your answer in late i.e. versions with digiplex ignition there is a crank and a cam sensor.

Ah! I didn't know that  :-\ I stand corrected sir....  ;) In fact I didn't know Betas came with digiplex....


Title: Re: Is coil failure the answer?
Post by: speedyK on December 16, 2013, 11:32:52 AM
There's no crank sensors on Betas. The problem must be either with the pickup sensor in the distributor or the electronic control unit or, of course, the associated wiring.
Mine is a 1981 Spider with the Bosch electronic control unit and carburettor.

It worked fine when I drive it into my garage. Just refuses to produce a spark now - which indicates a sudden failure of something. Don't think wiring could explain it.


Title: Re: Is coil failure the answer?
Post by: Thotos on December 16, 2013, 02:40:52 PM

Mine is a 1981 Spider with the Bosch electronic control unit and carburettor.

It worked fine when I drive it into my garage. Just refuses to produce a spark now - which indicates a sudden failure of something. Don't think wiring could explain it.

I thought so. Same ignition as on my Trevi and my Gamma. When I said wiring, I meant bad connections to the wiring. There's a plug on the control unit and if moisture got in there it could be that the connectors have tarnished and you are not getting good contact. Also the connector from distributor pickup system to the control unit. On my Trevi this wire has bullet connectors halfway (not sure if this is normal or someone replaced part of the wire). It's worth unplugging the connectors on the electronic control module and any to the sensor in the distributor and spraying the connectors with a good contact cleaner (Amberlube by Ambersil is the best http://www.arco.co.uk/products/3450003?gclid=COaSjuHutLsCFakBwwodqGsAHA (http://www.arco.co.uk/products/3450003?gclid=COaSjuHutLsCFakBwwodqGsAHA) also available as Servisol Super 10 from Maplin and other outlets http://www.ebay.co.uk/itm/like/231041737721 (http://www.ebay.co.uk/itm/like/231041737721)).

I think I may have a spare electronic control unit which I could send you to try if you want.


Title: Re: Is coil failure the answer?
Post by: speedyK on December 16, 2013, 09:25:28 PM
When I said wiring, I meant bad connections to the wiring. There's a plug on the control unit and if moisture got in there it could be that the connectors have tarnished and you are not getting good contact. Also the connector from distributor pickup system to the control unit. On my Trevi this wire has bullet connectors halfway (not sure if this is normal or someone replaced part of the wire). It's worth unplugging the connectors on the electronic control module and any to the sensor in the distributor and spraying the connectors with a good contact cleaner
I'll check through all the connectors again, though as it was sat in my dry garage, I can't see that corrosion should suddenly arise and take it from working just fine to not at all...

I think I may have a spare electronic control unit which I could send you to try if you want.
That is most kind  :)
I may well get back to you on that if I can't find another explanation for the problem. Are these control units the same on all the 2.0 litre Betas?


Title: Re: Is coil failure the answer?
Post by: Thotos on December 16, 2013, 09:31:53 PM
Are these control units the same on all the 2.0 litre Betas?

I believe so (except for the Digiplex cars as I was corrected above  :)) In fact I think they are the same for all cars that used the same Bosch ignition system. It's the same unit on my Gamma, at least it looks the same  :-\


Title: Re: Is coil failure the answer?
Post by: thecolonel on December 16, 2013, 11:54:09 PM
I had 3. Y Reg hpe and they all had slightly different systems.


Title: Re: Is coil failure the answer?
Post by: speedyK on December 17, 2013, 01:17:22 AM
Oh dear, that is not very reassuring...


Title: Re: Is coil failure the answer?
Post by: speedyK on July 01, 2014, 12:21:04 AM
In the end, I got an "old school" Fiat mechanic to come round and look at it.

I explained again how it had a fully charged new battery, new sparking plugs and a new coil.

He asked me to turn it over - I did and it turned enthusiaistically without the slightest sign of wanting to fire.

He then asked for a screwdriver. I asked what type and he said it didn't really matter.

He pulled a plug lead off one plug and asked me to turn it over again. I did - and it fired almost instantly and started running on 3 cylinders  :o :o :o

He then put the 4th lead back on and it ran as sweet as a nut.

In the cockpit, I hadn't been able to see exactly what he'd done, so I asked.
He gave me a sly look and said "Trade secret!"

Resisting the temptation to punch him, I persevered with my questioning.
He said that sometimes, when a car hasn't started for a while, it "needs a good run to earth" - and from what I'd been able to get out of him, he'd done this by shorting the screwdriver shaft (which was seemingly stuck into the plug lead) against the engine block.

My attempts with a plug lead near the block to check the spark hadn't had a similar result, so maybe he really did just complete the circuit and run it to earth which somehow "cleared" the system. I can't explain it better and he didn't seem to want to, but now it runs fine again.

Make of all this what you will, but I reckon the new plug leads and coil were not even necessary. So if you ever have a similar problem, give this trick a try!

Bloody electrickery - utterly baffling!  ;D


Title: Re: Is coil failure the answer?
Post by: peteracs on July 01, 2014, 01:40:32 AM
What an interesting solution. My first guess would be that there was some sort of resistance between the coil and the plug end and shorting 'cleaned' up the connection by allowing a belt of current through. Never heard of that technique and not something I would guess you should do too regularly, but obviously effective in this case....

Peter


Title: Re: Is coil failure the answer?
Post by: Per on November 25, 2019, 09:40:55 PM
Hmmm, I never came across electronic ignition behaving that way  ???  Live and learn......