Ignition type 1990 1.8 carb 8v GL

[macmillions]

Hello,

I have had a search through my Haynes manual and it appears unclear as to what ignition type I have in my 1990 1.8 carb 8v GL Golf. (Engine code GU)

I'm just curious due to renewing my spark plugs, the centre electrode appeared very pale (practically white), but the side electrodes were heavily sooted. (They are the correct electrode gap).

After a discussion with my g/f's dad who knows loads about cars he believes it could be the timing, caused by a possible siezing of the vacuum advance on the distributer. (Cambelt and tensioner changed this month, and set up using timing light). Would like to know what distributer to look at getting. but the contact breaker type and transistorised type look identical!

Can anyone assist?

Any help would be greatly appreciated as we are both stumped!

[kenney]

I have never seen the vacuum advance,seizing,but on the other hand not working due to a hole in the membrane,you can check this by sucking on the vacuum hose.The optical difference in the two distributors,is that the contact breaker dist,has the typical condensator on the side and the TST-H dist has not.Your descriptions of the plug suggests either the wrong plug, the engine is running too cold,or running too rich.

[macmillions]

Thanks for your reply.

The old plugs were NGK BP6E ones.
Not sure if these were the right ones, but due to the car running on when I turn off the ignition made me want to check the plugs to see if it was running rich or whatever. However, when I removed the HT lead from one of the plugs it bent the contact on the top of the plug and developed a misfire under heavy load. :aargh4:

So have bought some new Bosch Super 4 WR78 plugs, which are the right ones I'm sure.

Will check the distributer in a sec and will post back.

I've got another thread about the running on and have been informed it could be a number of things. I'll post on that thread as there have been some devlopments.

[macmillions]

After investgating it appears I have the transistorised ignition type.
Would you have said the old spark plugs were the correct ones?

[kenney]

The correct plugs for the GU engine with catalytic converter W6DO (101000000AB) and without converter W7DTC the NGK BP6E is the standard plug and is the right plug for the GU engine

[macmillions]

Sorry to sound a bit dense, but does that mean I have now fitted the incorrect plugs?

I went to Halfords and got the ones recommended in their booklet. It was a toss up between the NGK's or Bosch, but the Bosch ones were a couple of quid more and had an extra electrode, so I thought that would be the best option?

[kenney]

To be honest i don't know,if the WR78 is the correct plug for your engine,they are a so called 4 electroded super plug.If it was in the Halfords booklet that they fitted, then,they should be OK

[macmillions]

Ok thanks.
Yea I thought that too. If the book said it was ok, then I'm sure it will be fine. The car ran perfectly too, no misfire so the damaged plug must have been the problem on that front.

As for the distributer vacuum advance, I'll check that tomorrow when its daylight. When I suck on the vacuum hose, I'm assuming i suck on the end at the carb?

[kenney]

Yes

[Crasher]

Is the distributor cap black or brown or maybe brown with a black plastic cover?

[macmillions]

The cap is black. And I have double checked for the condenser and there definately isn't one. Also after closer inspection of the Haynes I'm positive its the TST-H one.

I checked the vacuum to the vacuum advance by sucking on the pipe (gross!) and my tongue stuck to the hose and I could hear the unit clicking in and out when I repeated it.

So that is obviously working.

Hmm... gotta try and work out why its running rich!... And cold...

[Crasher]

It won’t have a condenser, it is electronic ignition and a one piece black cap means the Ducellier or Valeo distributor which are much more unreliable than the Bosch, suffering from upper support bearing wear and failure of the vacuum advance unit. Either of these two failures means a new distributor and these are now obsolete from VW.

[macmillions]

Oh crap.

What are you supposed to do if it fails then?

Fortunately my vacuum advance still works as I tested by sucking on the pipe and could hear it clicking when I sucked, and my tongue stuck to the hose.

[Crasher]

Bump this later so I see it at home.

[macmillions]

Bump.

[Crasher]

Bit late I was in bed by then…

The vacuum advances for the Ducellier and Valeo still appear to be available, although they cost more than the obsolete Bosch replacement distributor did but the Bosch part may still be available from Bosch and will be available from reconditioners such as Excel.

[macmillions]

Sorry, I'm a bit confused now, do I have the Transistor or contact breaker ignition?

At least the vacuum advance is still available, even if it is at a cost.
I'm guessing the Bosch is the contact breaker system and the Ducellier and Valeo are transistorised?

[Crasher]

Why are you confused now, you have TCI-H electronic transistorised ignition, nothing I said in my last post changed that? Points were dropped in 85 and were only used on the 1.6 anyway.

The vac advance for the Ducellier or Valeo is about £170.

[macmillions]

Ah yes sorry, I've re-read the previous posts and what you had said did make sense. I must have read them too many times to make sure I was understanding it, then confused myself anyway!

£170 isn't exactly cheap!

If the distributer, or vacuum advance decided to kick the bucket, is there an alternative system?

[Crasher]

You can get a recon unit from Excel quite easily for less than the price of a vacuum unit.