Misbehaving
Misbehaving
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John042

Original Poster:

901 posts

185 months

Monday 28th May 2018
quotequote all
Wesley is being a painmadmad I experienced a misfire a few weeks ago and put that down to a different coil fitted so replace with the original. First 20 miles or so, faultless performance. After that intermittent cutting out. Starts again on the key immediately for a time then a repeat performance. Fuel starvation from vaporization when hot? Or have I got an ignition problem? I must admit I'm leaning towards electrical gremlins; as engine just cuts out, ignition light on but starts on the button. Any thought please, car is not to be trusted on any reasonably extended journey. Thanks J C.

mrzigazaga

18,655 posts

181 months

Monday 28th May 2018
quotequote all
Hi John


Thats a bummer...Check the distributor cap for hairline cracks and also inspect the rotor arm...Does yours have the blue ballast wire connected to the coil...?

John042

Original Poster:

901 posts

185 months

Monday 28th May 2018
quotequote all
Hi Mark, no mine has an external resistor mounted near the rad' doesn't seem to do a lot connected or not I really, thought I'd found the problem by swapping coils. I guess as you suggest working through the ignition system, dissy cap, rotor arm etc. Replacing items I guess is the best way although annoying when you can't find an obvious fault. I've attached a few pics' of; I assume is the ballast resistor and the coil connections. Could the ignition unit be at fault? Breaking down after prolonged running? A bit hit and miss Mark to try and diagnose by email.idea In a down moment I nearly bought a Reliant Scimitar! Cheers J C.






adam quantrill

11,609 posts

258 months

Monday 28th May 2018
quotequote all
What is the earthing arrangement like on the coil can? If it isn't great then HT pulses can get back into the primary side which could cause problems with electronic ignition. You could add an extra earth strap back to the block.

Also it's not a good idea to run 6V coils without the ballast resistor, but if it's 12V, then you are OK to delete it.

Lastly with all ignition problems run the engine at night and look under the bonnet for arcing and sort out any escaping sparks!


mrzigazaga

18,655 posts

181 months

Monday 28th May 2018
quotequote all
Hi John

The picture of the resistors on the rad mount are IIRC for the headlamps not the coil...its a blue ballast wire with a bullet connector in the middle, I think it runs from the spark module (large Motorcraft silver box) to coil..(Its been a while since I had my nose under a 280i bonnets I could be wrong...smile)...As Adam says as regards to coil and a good tip about checking for sparking under bonnet when dark.......Also how old are the HT leads?...You could check the vacuum diaphragm on the distributor, I think Dominic replaced his but I cannot remember the symptoms...

All I mostly had were fuel related issues on Delilah, there was a moment when I needed a new ignition switch but other than that.....

I will ask my Ford friend to see if he has known anything like it...I think this is now two 280i doing the same thing...


Ziga smile

KKson

3,460 posts

141 months

Monday 28th May 2018
quotequote all
adam quantrill said:
What is the earthing arrangement like on the coil can? If it isn't great then HT pulses can get back into the primary side which could cause problems with electronic ignition. You could add an extra earth strap back to the block.

Also it's not a good idea to run 6V coils without the ballast resistor, but if it's 12V, then you are OK to delete it.

Lastly with all ignition problems run the engine at night and look under the bonnet for arcing and sort out any escaping sparks!
Best tip ever....run the engine in the dark and see if the coil or HT leads are breaking down. Just because stuff is new doesnt mean it's less likely to fail, especially given the st quality of imported Chinese items. My money would be on the ignition amp breaking down or if not then the king lead from coil to top of dissy. ALL issues I've had with both Wedges have always been ignition related.

John042

Original Poster:

901 posts

185 months

Monday 28th May 2018
quotequote all
Thanks Mark , Adam. Often wondered at that resistor? The maddening thing is the perfect performance until a few miles. Certainly another earth from the coil mounting to the block, first move. Replace dissy cap, leads and rotor arm. I will check the coil wiring Mark but can't remember seeing any bullet contectors in the wiring. Fuelling has always been at the back of my mind since 20 years of black crud in the tank fuel lines. Hopefully eliminated with a new fuel pump inline filters. All seemed to remained clean over the last 2 years. The immediate starting after cutting out is the puzzling one. Thanks Chaps for your constructive thoughts and suggestions,

mrzigazaga

18,655 posts

181 months

Monday 28th May 2018
quotequote all
Hi John



If there is any crud in the fuel then it could be causing an issue as the Cologne is sensitive to cruddy fuel..Has the bulkhead filter been changed?....

350zwelgje

1,820 posts

277 months

Monday 28th May 2018
quotequote all
Coils that are not ok, brake down when getting hot after running the engine for some time (20miles in your case when departing with a cold engine?)
So if your old coil is not ok, these symptoms you describe look like it.
Cooling the coil down with an ice-pack or something else that brings it temperature down, then running ok could prove it as well.
Is the new replacement of the same specification? Needing ballast, etc? If not it will not do a proper job.
Next point to check would be an ignition amplifier, if it has one (not familiar with the 280i engine). As the same could happen.

Rob

mrzigazaga

18,655 posts

181 months

Monday 28th May 2018
quotequote all
They have a spark module which is kind of similar to an ignition amp...the rarely fail...not ruling it out but could be as said...wrong coil...you do need one with a ballast wire...Can you take a pic of the coil and spark module area please...

Ziga smile
Sorry... the original were Dura-spark...Im sure Motorcraft were later versions...Dont quote me on it...
https://www.ebay.co.uk/itm/FITS-FORD-CAPRI-1994-19...

John042

Original Poster:

901 posts

185 months

Monday 28th May 2018
quotequote all
Thanks all for the relies. Yes Mark all flters changed over the winter with no sign of "crud" in them including the inline filter between the tank and pump. As suggested heat culd be the problem. The new coil I got came with an external balast resistor. When fitted without the resistor developed the same problem so original coil was refitted. I've just orderd some ignition leads and am sourcing a dissy cap and rotor arm. Will post pics of the ignition unit and coil. Cheers J C.

John042

Original Poster:

901 posts

185 months

Tuesday 29th May 2018
quotequote all
Hi Mark please find attached pics of areas of interest.








I have an additional coil as the one in the photo, although new did display the same fault after a few miles. New leads, Dissy Cap and Rotor Arm on order. The one taken off doesn't look that clever? Like to think that's the problem. I've cleaned all the connecting plugs to the ignition unit and dissy. Not the best way to fault find but other than the ignition unit it's self I must have eliminated most of the ignition system? J C.

mrzigazaga

18,655 posts

181 months

Tuesday 29th May 2018
quotequote all
Hi John


My electrical knowledge is pants but it sounds like you may have the wrong coil...as well as a badgered rotor arm...that in itself would cause issues...

I found this on a Ford forum...

"Firstly, the ballast resistor is a long thick grey wire taped into the loom - it runs along the bulkhead roughly starting from the rear of the servo behind the engine and down along the passenger side chassis rail to almost beneath where the coil is.

When the engine is running the coil takes a 9v(ish) feed (someone please correct me if I'm slightly wrong) via the ballast resistor wire then on to the distributor. An engine running a ballast system uses a 9v coil or 'ballast coil'.

When a ballast system engine is being cranked (starting the car key position III) the ballast wire is actually tempoarily bypassed and the coil gets a breif 12v feed resulting in a bigger spark. When you let go of the key (back to position II) once the engine has fired the feed switches to the ballast wire and 9v to the coil and onto the distrubutor.

The idea behind this is/was to help engines running points to start on cold mornings by provideing them with a bigger spark.

Now - this leads to the difference in coils - a 9v 'ballast coil' is a low resitance type (designed to work with a ballast wire) if it gets a constant 12v feed it will burn out. 12 volt coils are designed for non ballast systems and can cope with a constant 12v feed they are sometimes called 'high resistance coils' or 'non ballast' coils - be aware though, they have a resistance built in so will still only give around 9v to the distributor.

If you fit a 12v coil to a ballast system you will get a weak spark (too much resistance). Just as if a 9v coil is fitted to a non-ballast system you will get a massive spark (again, this is how the ballast system aids starting with the key is pos III) until points and coil both burn out prematurely.

The ballast wire played up on one of my cars - it would start when cold but once warm would just crank and crank with a very weak spark. I long since did away with points (run a luminitation optronic system) so I opened up the loom, cut out the ballast wire - replaced this with normal wire and fitted a 12v coil - problem sorted. I don't think replacement ballast wires are available but I know Burton do a replacment resistor you can fit instead.

As your car is a mk3 I'm 99.9% sure it will run a ballast system - with a volt meter and the igintion on you can test test power going into the coil both with the key in pos II and (with someone cranking) on pos III - saying that if the problem is intermitant it can really have some games with you - mine gave all sorts of readings but in the end the ballast wire was the culprit.

IIRC - If you take a 12v switched feed from the ignition (gets 12v with the key in posII) (there is just such a spare terminal on the fuse box) and feed this to the + on the coil and the problem is cured, it is likley to the resistor at fault."

I know that the Wedge wire was blue and not grey...


Hope this helps...


Ziga smile

Grady

1,227 posts

276 months

Tuesday 29th May 2018
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The Dura-Spark ignition module can go bad with gremlin-ish electrical results. Replacements are available but make sure you get the "blue" one (the color of the plastic where the wires enter the box). Over here, a genuine MotorCraft one was ~$100. I bought a name brand one for ~$35, cheaper ones were available. I'm sure they are all made in a factory in China.

John042

Original Poster:

901 posts

185 months

Tuesday 29th May 2018
quotequote all
Thanks Mark I've digested most of thatlaugh Rewinding Wesley about 12 months ago it had a habit of not starting when hot, very embarrassing at MOT time! With help it was found there was no supply to the coil when hot. Once cooled down, instant starting. That problem was sorted by a different coil maybe masking the initial problem with the ballast wire. I think you may have put me on the right track with the ballast resistor wire. The coil in the photo is a 12 volt one but came with an external ballast resistor. So your advice on running a 12 volt ignition switched supply I reckon is the way to go with a 12 volt coil. Are there spare connectors on the back of the fuse board for a supply Mark? Incidentally I forgot to ask what's the headlight resistor for mounted near the radiator? Cheers Mate you have cheered me up.bouncebeer John C.

mrzigazaga

18,655 posts

181 months

Tuesday 29th May 2018
quotequote all
Hi John


All that info was taken from a Ford site so most of it is relevant to a Capri, especially fuse box and colour of wires..

IIRC my ballast wire was already in the loom and was blue..you should have one on yours..somewhere?...As said mate...my electrical knowledge could be written on the back of a stamp with loads of licking room left...hehe

Maybe a 280i wiring diagram from the Wedge manual although that is probably as useful as a fart in a space suit...smile

I think that resistor had something to do with dim-dip ....ignore that for now...

Do you have a Wedge manual?

John042

Original Poster:

901 posts

185 months

Tuesday 29th May 2018
quotequote all
Thanks Mark, a quick look didn't reveal any loom from drivers side to passenger side on the bulkhead. Most of my wiring seems to go underneath. However, your suggestion of slaving a switched 12 volt supply is the way to go. Yes I've got the "Bible" so will follow that and my trusty multimeter. The ignition unit will be the last resort but one to bear in mind. J C

mrzigazaga

18,655 posts

181 months

Tuesday 29th May 2018
quotequote all
John042 said:
your suggestion of slaving a switched 12 volt supply is the way to go.
That info was retrieved from a Ford forum...So its my suggested suggestion...(Dont hold me to it...)..smile

John042

Original Poster:

901 posts

185 months

Tuesday 29th May 2018
quotequote all
No problem Mark, good idea though when as in my case cutting into the wiring loom. I agree the Heath Manual does leave a lot to wonder at. A cholce of wiring diagrams none resemble yours. J C.

mrzigazaga

18,655 posts

181 months

Tuesday 29th May 2018
quotequote all
John042 said:
No problem Mark, good idea though when as in my case cutting into the wiring loom. I agree the Heath Manual does leave a lot to wonder at. A cholce of wiring diagrams none resemble yours. J C.
hehe

Hope you sort it matey...smile