h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Hi Rains,

You were recommended as somebody who knows a thing or two about VWs, are your brains available to be picked on the subject of ignition timing on Mark 2 Golfs?


Queegle

Hi Queegle ,

It's a long time since I've fiddled with Mk2 Golfs, I'm afraid.... my memory's a bit rusty on the specifics! But fire away and I'll try to help .



Rains

Ooh brilliant! I'm not sure what the exact question is, as the other half (& Mk2 Golf owner) isn't here, but I think it's just along the lines of "how do you time the ignition?" or "how do you set the ignition timer?".

I'm sure one of those questions will be applicable to how it all works. I just make 'em look pretty on the outside, he get's 'em working

Making it look pretty is important too .

My Golf was a fuel injected one (a GTI) so the ignition timing was all controlled by the Engine Management ECU... my current car is a diesel so has no need for the ignition timing to be set (I can explain if you like, but I don't want to sidetrack!). Crumbs, I've just realised it's five years since I had my Golf .

One way to adjust the timing is to fiddle with the distributor - the HT leads come out of this to the spark plugs in the engine. The distributor actually delivers the spark, so any ignition problems could be due to a distributor problem.

If you actually need to *set* the timing, this is where my knowledge is hazy through lack of use . You need to find TDC (top dead centre) - a mark should be somewhere reasonably visible, either on the crank pulley or the flywheel or similar on the engine itself. Ignition timing is usually measured in degrees before TDC; the degrees are in this case the actual measurement of how far the mark is from TDC when the spark actually happens.

Unfortunately, I can't remember much else and even Google is being uncooperative and not providing anything specific to Golfs . If I still had my Golf Haynes Manual, I'd send it you!

A good run-through with some good explanations (although the precise method will vary for your car) is at http://www.mgcars.org.uk/cgi-bin/gen5?runprog=mgoc&p=emg/basic5.htm

I'm sorry I can't be more specific - I don't want to hazard any guesses as to how to do it in case I'm really wrong and I don't want to lead you down the wrong track - but I hope I've been some use.

Thanks Rains, he's gonna have a look at that website.

Having spoken to him, he knows how to set the ignition timing as standard, but apparently in order to tweak it even further you need to unplug certain sensors within the engine. Finding out exactly what to do is proving very difficult. We had a garage 'tune' the engine, but the poor car hasn't had as much welly since.

Thanks for your help, he's going to have a go and see what happens!

Ah.....

In that case, he should definitely check out the lambda sensor which monitors the oxygen content in the exhaust gases and then feeds back into all the fuelling stuff.

There should also be an EGR valve (exhaust gas recirculation) valve which pipes some of the exhaust gases back into the cylinder. Normally unplugging this makes the car run a bit better, but if you do that I'd plug it back in for MOT time! It's nominally there to improve emissions.

There may also be another sensor which monitors the amount of airflow actually going into the engine, which also feeds into all the fuelling stuff.

They're the main culprits which will be affecting it - there's probably also a knock sensor in there somewhere too which can affect fuelling and does influence ignition timing.

You'll have to let me know how he gets on, I'm all curious now . good luck!