1.9DG running problems - dizzy?

[gjy55split]

Since my last postings re not running on no. 3, we got it running almost perfectly but not 100% sure how!!.
It went through a phase of only running on no2 and also filling the crankcase with petrol.
After messing around with seemingly everything, including backing off valve clearances and retarding the ignition, it was finally running.
Now, it would seem for no apparent reason, it's gone back to only running on one cylinder, now it's no. 4.
Spark is weaker and or intermittent on the other cylinders.
I'm guessing this is a distributor / amplifier problem. Any tips on checking / rebuilding please?
Anyone got a spare dizzy / amplifier module for sale?
Thanks in advance.
Gareth

[Aidan]

contact Mick at Elite VW he'll be able to get to the bottom of it I am sure

[ghost123uk]

Hi Gareth,

Firstly,

and also filling the crankcase with petrol.

What did you do to fix this potentially very serious (if left un-fixed) problem ?

Then,

It went through a phase of only running on no2, Now it's gone back to only running on one cylinder, now it's no. 4.

An engine is very unlikely to run at all on one cylinder and even if it did it would be dead easy to trace what was going on *if you had some experience of such matters*. If as it seems (no disrespect intended), you haven't, then I agree with Aiden, you need some professional help.

Spark is weaker and or intermittent on the other cylinders.
I'm guessing this is a distributor / amplifier problem. Any tips on checking / rebuilding please?
Anyone got a spare dizzy / amplifier module for sale?

If it only weak on one (or 2 or 3) cylinders, then (logically) it can only be Leads, Cap, or plugs.
If you are going to do this yourself, you need to be properly methodical, not just go around "trying this and that".

[gjy55split]

Thanks for reply.
I'm - clearly - no expert but am more than happy to work my way through engines. We also did have it running nigh on perfectly.
New fuel pump fitted in attempt to cure fueling issue. Carb - webber, I know, get rid of it - also stripped and cleaned.
Only one lead was fitted in dizzy cap, it was only running on one cylinder.
Spark is now weak on all other cylinders. Everything is the same as was when running fine.
Because it only ran on no. 2 prev. and now it's only running on no. 4, I'm pretty sure it's an intermittent dizzy / electrical problem.
We'll get there, just appreciate a little guidance if this has cropped up before.
Thanks.

[ghost123uk]

Because it only ran on no. 2 prev. and now it's only running on no. 4, I'm pretty sure it's an intermittent dizzy / electrical problem.

Please remember, a dizzy, amp or coil cannot cause an OK spark on 1 or more plugs, and a weak spark on others.

If I can try and explain in words, the "health" of the sparks HAS to be the same up to the distributor cap because that lead in the middle of it has ALL the sparks in it. The dizzy cap and rotor arm then simply feed (mechanically) the sparks to the appropriate HT lead and plug. So if 1 or more cylinders have a weak spark, it can ONLY be due to a fault in either the dizzy cap, an HT lead or a plug.

We'll get there, just appreciate a little guidance if this has cropped up before. Thanks.

No worries

[T25Convert]

Hi,

I've no idea how you've managed to get it running with one plug lead on!!

As you seem to be getting consistantly good sparks on a single cylinder it suggests there is nothing wrong with the ignition amplifier side of things, as you'd expect all sparks to be poor (as an aside, how are you judging what a 'weak' spark is?).

To check this side of things run a lead with a spark plug on the end directly out the coil, and earth it. Remove plug from hall sender and stick a bit of wire in the middle hole of the connector. Taking care and switch the ignition on. Drag the wire from middle hole of hall sender across an earth, and you should get spark(s) out the spaking plug (if you don't check the earth on all items first!) If you do the coil / amplifier area is all fine.

Suggests the issue lies with getting the spark to the plug, so rotor cap or leads are the most likely issue. Have you tried the simple suggestion of swapping the plug and lead form another cylinder to see what effect that has? New set of plugs, leads, cap and rotor arm?

Have you reset everything you fiddled with to getting it running before? Are the valve clearenaces reset? Have you put the timimng back to what it was? If this is a suddne onset issue (which it seems to be) it is unlily to have been caused by the valves / timing, more likley the fialure of a component.

Cheers,

Alex

[ghost123uk]

New set of plugs, leads, cap and rotor arm?

Have you reset everything you fiddled with to getting it running before? Are the valve clearances reset? Have you put the timing back to what it was? [= where it should be = 5 deg btdc]

Cheers,

Alex

And again =


(red bit by me)

[T25Convert]

GHOST123UK - looks like you typed faster than me! Seems we're of the same opinion though!

Cheers,

Alex

[ghost123uk]

John

[gjy55split]

Thanks all.
Not much time tonight but checked one lead and plug at a time e.g. 1 lead on no. 1, then moved to 2, 3 & 4. Repeated for other 3 leads/plugs.
All worked fine individually but when all 4 connected, spark is weak on 1 & 3.
Now running on 2 & 4 only, no petrol in crankcase.
New cap, plugs, leads and rotor arm ordered tonight.