Scirocco Register

First off, apologies for posting this here as my problem could span engines, fueling and electrical categories in the help forums so couldn't decide which heading to post under!

Car is a standard 1.6 Mk2 Scirocco GT with standard carb'd engine with 25k on the clock. Fuel filler neck is brand new and was only replaced as a precaution as original wasn't rotten and there's no crud in the tank or fuel filter.

Car hasn't been used regularly since September 2008, but the engine has been started and run up to operating temperature every few weeks since. After running the engine for some 20 minutes on the driveway simulating driving as best I could, the revs became lower and weaker over a period of 5 seconds and the engine cut out and will not restart.....it turns over and every now and again will try to cough into life for a split second but never fires.

I'm now at the end of my tether with this because since this occurred I have done all of the following / fitted them to try and sort the problem out:

Fuel tank drained and refilled with fresh fuel
- New fuel pump
- New fuel swirl pot
- New rubber carburettor mounting
- Pierburg 2E2 completely rebuilt and reset by a professional with all usual suspect parts renewed (originally thought the float had stuck as engine ran for short time after carbtaken off and refitted as movement could have released it). ps carb ran perfectly before this problem and should do again.
- New spark plugs
-New ignition amplifier module

Dizzy cap and rotor are fine. Fuel is pumping through and wetting the 'plugs and I'm getting a spark at all of them Was also assured by a local garage that the belt timing and dizzy timing are ok.

Come so far (and spent a fortune) but still no joy - aside from what I've already done, has anyone any idea of what the problem is likely to be? Suggestions gratefully received!

How do you know that your dizzy cap and rotor arm are OK? Are they new? How old are your HT leads.

It seems from your post that you have replaced most of the fuel side of things, so theres only air and spark left.

I'm no expert but Dizzy caps and rotor arms are fairly cheap and might be worth a try.

What about the distributor itself?

And the coil?

And HT leads?

And your battery and alternator?

I'm also informed the ballast resistor might be worth checking.

Did the problem occur whilst driving and then you tried to replicate it on your drive, or were you just simulating driving on your drive for some reason? Have you used the car on the road? If it's been sat for ages and not run properly, I'd have thought there'd be a good chance the battery isn't properly charged. If you're just running it on the drive, the alternator won't be able to charge the battery effectively (if at all).

I had a very similar problem, a vacuum hose from the brake servo had popped off the non return valve, if that makes sense, i would check that first before spending any money

Cheers guys for your initial thoughts.

In response to your questions, the car has not been used on the road. My 'simulated' driving just involved letting the revs climb at little to about 1500 on the revs every 30 secs or so, but not revving it. Engine cut out 20 minutes after I'd started it from cold and so was off choke and hot.

Battery is charged to the brim and hasn't been (and wasn't at the time of the cut out) flat. It's a freedom battery with the 'eye' on the top facing - it's bright green indicating full charge. Dizzy cap and rotor were bought from VW and have done approx 1000 miles on them and are like new. HT leads are Bosch that were fitted at same time as the rotor and cap, so should be ok.

Not tested the coil. The alternator appears to be ok - I'm assuming that if it wasn't the car would have run the battery down to flat when it cut out, but the battery wasn't flat when that happened.

Cheers NiceOne for the tip about the servo vacuum hose - I'll check this out. Is the ballast resistor the same thing as what some people call the ignition module that sits in the bulkhead?

As for the ignition system generally, I am getting a decent spark from an earthed test plug. This problem first hapenned in August 09. As the car was beached at the top of a steep driveway I called in a mobile mechanic to look at it - bad move as he unbolted the dizzy then subsequently left the job 'because he couldn't stand me watching him'!. Obviously, this made things worse, so I forked out and got the car trailered to a local garage and I asked them to investigate but sort out the dizzy timing as well as check the belt timing. They did this (which I why I'm assuming the timing is ok). Still wouldn't start, but it did do after they removed the carb to check the state of the rubber mounting - this is why I went town the carb rebuild route as I was convinced the float had stuck and that the jolt of them putting it on a bench had freed it up. because it was running, the garage stopped work and gave me the car back. Cue November 2009 when I srtared it up in the same way as described only for it to slowly cut out again.

I know that they've said that the timing is supposedly ok, but now I'm thinking that this needs to be checked again - I'm getting fuel and spark so why no bang?!?!? I was planning to fit a new dizzy shortly in any case as I'm in the process of getting my engine bay smartened up - now wondering if I should get someone in to fit this and set the timing again at the same time? I've heard that belts can jump teeth, but is it really possible for a distributor to fall out of timing all of it's own?

Also, I've got the chance to borrow a compression tester tonight - hope to God that comes back ok, though I'm guessing it would on a low mileage engine. That said, it's just another something to rule out of enquiries!

where abouts in the country are you? might be someone near who can come have a look?

Well, I did manage to check the compression of sorts - trying to keep the testing guage steady was impossible as the engine was constantly trying to blast the guage out. It ended up sending the rubber seal at the base of the guage rod so far up the rod that it's now impossible to get off - whilst the blasting made it hard to see the reading I guess that at least I'm getting compression, so I think this can be eliminated from enquiries.

I mentioned earlier that the garage had previously ok'd the timing at the belt and set the dizzy timing, but no matter how much I think about this I keep going back to one thing:

I'm getting sparks & fuel so it must surely be TIMING. Unless this is checked again I don't think I can move forward on this.

Next step is to order that new distributor and get somone out to fit it and set the timing. Haynes does mention that the dizzy can go faulty but still generate sparks, so putting a new one on is probably the gamble that I must now take.

Checked the vacuum pipe going off to brake master cylinder and it's fine. I'm in Rochdale, Lancs.

If your timing is out, then changing the Dizzy won't help if the cambelt has been put back on wrong. Your dizzy might well be pushing a spark at the right time, the compression might well seem right, but if your camshaft is out by a tooth, that's 12.5 degrees (I think? Sure someone can confirm the correct amount) so your spark may well ignite, but completely at the wrong time, which will result in lumpy running.

That's the first thing I'd be checking, along with double checking that when your engine is TDC, the location of the rotor in the dizzy. Both camshaft and dizzy are easy enough to check as it's mainly visual once you have your crank at TDC.
Personally I never take a garages assurances that something is "right" when clearly it's not. It's only right compared to their own knowledge, which may well not be right in the first place. Does that make sense? (and I'm not trying to say mechanics are always wrong... just that on this occassion they may well have got it wrong)

Funky Diver wrote: Personally I never take a garages assurances that something is "right" when clearly it's not. It's only right compared to their own knowledge, which may well not be right in the first place. Does that make sense? (and I'm not trying to say mechanics are always wrong... just that on this occassion they may well have got it wrong)

if they are even a half decent garage, they should have a copy of autodata or similar. but it wouldn't be the first time i'd seen the marks on the dizzy confused.

check ignition timing is roughly right thusly:

turn engine so TDC mark lines up (crank or cam, don't matter which) take the dizzy cap off. the rotor arm should now be pointing at a small nick in the rim of the dizzy body. if it is roughly 1/2 turn out, rotate the engine 1 complete turn and try again.

Definately sounds like timing.
Check the timing marks on the Crank, Water pump and cam pulley all line up like they should.

Been a busy week, but ultimately I'm still no further forward!

My main suspect is the dizzy - I've moved the plug leads 'round, but this made no difference. Interestingly, once I'd refitted everything up back the way it was and tried to start the car, rather than the car just cranking with the odd 'phut' from the engine, it ran extremely roughly / weakly without touching the accelerator pedal for nearly 3 seconds!. Thereafter (probably flooded a bit), it didn't do this, but there was much more of an effort from the engine in terms of trying to fire.

As previously mentioned, the cap and rotor have seen little use and are ok. The rotor is the round shaped 'restrictor' type (as it's described in Haynes), not the normal 'arm' shape.

I took out the inspection plug from the flywheel casing, put the car in 3rd gear and pushed it so that I could get what I believed to be the TDC marker on the flywheel to the middle of the inspection hole (marker was a dimple in flywheel). I then went back to the dizzy and took off the cap to see where the rotor was.

Haynes suggests that there's a notch on the rotor that should line up with the notch on the lip of the dizzy barrel. There isn't a notch on the rotor, although there is a small 'braille' type marker on it, which I assumed to be the same thing. This marker was about 5mm to the left of the notch on the barrel - I could manually turn the rotor to the right against the spring to try and line it up againt the spring loading.

I'm getting the impression that it's the dizzy, though not sure. Other suggestions have included a leak in the inlet manifold, though this isn't really a job I want to undertake speculatively before changing the dizzy.

You tried turning the rotor, but did you slacken off the dizzy and move the dizzy body round to line up the dimple?

Just undo the nut holding the dizzy clamp, and rotate the body around in hte direction required to line it up. This will at least get you somewhere near TDC on the dizzy too. The body will move whilst the arm should stay still, being connected to the dizzy shaft :D

Don't forget to tighten the clamp up again ;)

I was going to change the dizzy as I'm in the process of detailing my engine bay. Mine has the metal earthing ring / collar fitted and I want to maintain originality, not have later black plastic sheath over the cap.

Went to VW and quoted the part no. of my dizzy, which is 026 905 206 AD. However, what came was part 026 905 205 AF. The cap was taller and winder (i.e. greater circumferance) than mine. The rotor was the arm type. Wasn't too bothered about that until I tried the collar over the new cap at the counter and I wouldn't fit, so I decided to leave it for the time being.

As I'm wanting to change the dizzy for the aesthetics, I don't want to shell out £220 for a new dizzy, fit it, and then the car still not start and be left with something that still didn't look right. Got my local auto electrics shop searching for the original unit direct from Bosch, although their online catalogue suggests that it's about tobe dropped. I'll find out on Monday and then I'll decide - I don't want to fit a cheap copy part, so I might have to settle for losing the earth screening ring after all....

Anyone know of decent places that rebuild dizzys - parts seem to be available from Bosch to recondition my original.

I had this problem and took my Mk 2 (carby version) to the VW genius up the road - The float in the carby slowly filled and sank....a new float fixed it. I know you've probably rebuilt the carby 5 times by now (!!!) but was the float ever checked?
Good luck with it. BTW, I backed into a solid timber pole and had the a deja-vu of the whole 'splutter and die' thing until I tapped the carby quite firmly - seems the Piersburg can lock up - and subsequently unlock - the float after a bit of a thump. No damage to the Mk2 thanks be to the reversing fairies.

The carb float theory was what kicked off me getting the Pierburg rebuilt by a specialist. Amongst the other new bits I had fitted, there's a new float & needle fitted as well. The guy who rebuilt it said the flat chamber was clean as a whistle, so there there was no reason for it to stick. This is why I've no largely discounted the problem being caused by the float in the carb.

I've got a mechanic to come out to it on Friday to check out the dizzy and timing (I'm convinced the problem is timing-related now). I've already tried totating the leads by 180 degrees and the car makes even less of an attempt to start when this is done. Problem has been that there's so many marks on the flywheel that I'm having trouble picking the one that actually is TDC (i.e. not like the picture in Haynes). This is why I'm getting someone out to it who can say for sure whether the dizzy timing is out and set it up properly again.

Other suggestions have included a leak in the inlet manifold gasket - not a daft idea at all, but I don't think it's this as if a hole had opened up causing the engine to stop it was never have restarted again when it went into the garage last year (holes don't plug themselves!).

I'll let you know how I get on.