BXProject

I've asked this already but can't find the thread/answer:

The 16v would misfire above 4000 rpm, rev counter affected also. I can't afford to replace the ignition setup, but Doc mentioned a likely cause: either coil or coil module (aka amplifier....?) What's the more likely? (plugs and leads are good. Dizzy and rotor could prob do with being renewed but I think are servicable for now)
Being slightly anal I'm after original eq, i believe the amplifier/module is Bosch? What about the coil? Does it really make that much difference?

I think the 16v needs to be pressed into service so that I can take some time to get the TD sorted and do my project.

Going back into history (I've run diesels scince 1990) coils don't fail that often, but when they do, those are the syptoms.
Does the system retain the rotor?? If so the cap and rotor need a thorough clean to check for wear and cracks. If they are still available they won't cost that much, but I thought the innards were replaced my an ignition module.

It still uses the rotor to distribute the sparks though. My money would be also on the coil, is it worse under load?

I had exactly the same problem on my bike once (it didn't help that a second hand coil also showed the same symptoms), most memorably whilst accelerating hard from a set of traffic lights when trying to impress a girlie. The engine cut out at about 5k rpm in first, sucked a load of petrol into the exhaust so that when it cut back in again (throttle still fully open) there was a huge backfire and I inadvertently pulled a wheelie, followed by the mother of all tankslappers when I touched down again...

I don't think the girl would have been impressed.

Probably soiled her knickers, if she was on the back.

at Matt. You are one of those people that funny things just happen to mate! Quality image in my head!

Think it is under load Matt yes, so that points coil wards then. I'm also assuming coils are much of a muchness, so make wise I should be pretty ok to takes my pick.

I think it's a half way house Phil, old school distribution but new fangled leccy control. I'll have a good inspection of them, but I'll start at the coil as the most obvious culprit and go from there.

Out of interest, what would symptoms of early/intermittent failure of the CAS be?

Philhod wrote:Probably soiled her knickers

I don't know, but I nearly shat myself. It was the one and only time I've ever got the front wheel off the ground, and I'd only just passed my test!

the coils cheap enough, and easily available, fits all manner of stuff, not just valvers.. BUT, bear in mind a failing amp will give the same symptoms and take the coil out eventually.

CAS rarely fails, like, hardly ever, usually shit in the plug. But they usually work, or they dont. they can occassionally go a bit ape shit when hot and gove spurius readings, but that results in the engine not running, at all.

and I'd only just passed my test!

Hadn't had time to learn to keep the front dead straight before landing then.

I had loads of petrol stuff before 1990 but I never once had a coil fail.

Yeah that's what I meant Bandit. My Opel Manta was like that but I swapped it for a Lumenition optical thingy with a chopper replacing the rotor arm. It was the dog's after that.

Thanks Doc, see if I can get the both then, I've never touched them since I had the car

Philhod wrote:I swapped it for a Lumenition optical thingy with a chopper replacing the rotor arm. It was the dog's after that.

I don't get that, surely you mean it replaced the points, because the rotor arm is used for moving the spark between cylinders! Unless it also modded the high voltage side to the wasted spark principle......

Lumenition was the first stage into electronics. In place of the points you had a light unit which screwed into the baseplate and was shaped thus [ the top part of the C had a beam of light, reflected by a tiny mirror on the bottom arm of the C. there was a small box up the back of the C, with several wires coming out of it, exiting the cap where the LT wire normally came, 2 of the wires plugging in to the LT and some to the coil.
In place of the rotor arm was what was termed as a chopper. A 4 bladed plastic top with connector to the cap brush and a base shaped exactly like a normal stepped rotor arm and just pushed on. The blades cut the beam as they passed between it and triggered the spark.
With the ign timing set with a gun iot produced an excellent spark under all conditions with no bounce or tracking.

but, but but..... I still couldn't see how it replaced the rotor arm for spark routing so I looked it up on the web and found this useful page:

http://www.newtronic.co.uk/new/main.php/optron/

It is as I thought an optronic replacement for the points. The normal rotor arm is still used above it.

So it was....... well I was working from memory and it was over 30 years ago an ...an...I'm no longer into petroly electrickery stuff

I had lumenition on my mk3 cortina and my 130 lse skoda , it was worth its weight in gold, a good solid constant spark and no points or condensor to worry about

Got it on the Stellar - originally fitted to the 1.6 engine and then transferred to the V8 with a different fitting kit. (Look Phil, a rotor arm! )



I think it's a fairly safe bet that Bandit doesn't have one on his valver though...

A 4 bladed plastic top with connector to the cap brush and a base shaped exactly like a normal stepped rotor arm and just pushed on. The blades cut the beam as they passed between it and triggered the spark.

The later ones utilised the original rotor arm. As far as I can remember mine came as a unit with a narrow headed rotor arm replacement with built in chopper. This was 1975

Philhod wrote:
The later ones utilised the original rotor arm. As far as I can remember mine came as a unit with a narrow headed rotor arm replacement with built in chopper. This was 1975

It doesn't make any difference does it? The point is (excuse the pun) that the Luminition is all about improving operations by replacing the (low voltage) points. Whether it is new or it is old (1975) it plays no part in or improving the High Voltage Distribution task of the distributor itself.

Incidentally, my BXGTi does not have a rotor arm or even a distributor. It works on the wasted spark system which has been very good in all engine operations to date. Elimination of the distributor is a good thing especially from the problems they can cause on damp days (they can become hygroscopic with age)!

`That's the achilles heel of all inefficient petrol engines. They need sparks and all sorts of electrickery to get them going and usually it's the first thing to let you down.

AA and RAC report that over 70% of breakdowns are caused by faulty ignition circuitry.

After I had had it in for 4 years, we went on holiday to Northumberland. The chopper grabbed the wires twisting them round inside the cap till they snapped and we stopped.
Fortunately There was a Vauxhall garage in Seahouses where it happened and I bought some points and Lt cable and converted it back till we got home

Hmmm, I wonder whether you have any experience with magneto ignition systems Phil? I'll start a new thread...

Remember when my mechanics teacher first gave me a mag to play with.
That's when you learn that they give full power spark even when you turn the shaft by hand