Engine sluggish

After a number of years of sitting in the garage, with lots of help I have managed to get my 1800 mk1 gti mot & running, however, it struggles to idle from cold start and when running when you depress the accelerator it is sluggish. It does run but lacks the gti performance. I've no idea where to start to put this right! I'm no mechanic. Can anyone suggest anything that may be the cause or the type of place I need to take it to diagnose this please.
[Suggestions so far have been a sensor not working? Injector issue?] Thanks.

What petrol are you using and how old is the petrol in the tank?
Super unleaded is best for the GTi.

How long and how many miles have you done in the car?

How old is the spark plugs, HT leads, dissy cap, rotor arm.

Did you change the cambelt and are all the timing mark lined up properly?

Thanks for the reply. Had the tank pumped out and Shell super plus put in, the car has covered 34k from manufacture, yes 34k, the plugs could be 6+ years old but haven't done any real miles - checked tonight and they are light fawn colour, HT leads were replaced at same time, dissy cap/arm i've just cleaned them up and they looked to me ok, however, I have been trying to source a new Bosch one just to see if it makes any difference - cant find anyone selling them. cam belt was replaced about 5 years ago and it was running ok then, the last time it ran well.

I use Bosch or Beru in my car both good makes, ebay might have Bosch stuff or search for a local Bosch motor-factors as that's where I get my stuff from as they order it in.

Good place for hard to find stuff.
http://www.vwspares.co.uk/g1electrical.php

I would change the cam belt and tensioner, they will degrade over time and for the cost of a new belt its worth it. Conti belts is what I fit.

https://www.carparts4less.co.uk/timing-belt

https://www.carparts4less.co.uk/tensioners-idlers-and-dampers

I would also check the timing and what was the CO setting, they usually give you a print out when they MOT the car?

 

I'd do all of the above but remember extreme low mileage can be more hurtful than and engine that's pushed frequently.

So what I would do even before the above is take it out having checked all the levels and drive it hard on the motorway.
Don't be scared drive it for a good 100 miles round trip, rev it hard through the gears after it's warmed up.

Leave it overnight and see how it behaves the next day, you just might be surprised and as many of us can vouch for, these engines are near bomb proof and seem to like being pushed.

They' were not built to compete with a slug carrying some heavy shopping home!    

No shopping in my boot! Its been sitting in the garage for a while, but, I'm making an effort to get as much done before the winter. Had 4 Pirelli P1 tyres fitted today, not as nice as the old cracked P6 that were on, but ok.
Thanks for all the help - When starting up this morning I noticed that the oil light, very dim, lit up for about 5 mins?? Its got a new filter/oil and i've checked oil level tonight all ok, any ideas why this came on?
The sluggish -ness, is hard to describe, but the car is fine for driving around, but when you want to push on, its not there, like the old twin carbs, mine is missing the second one?? It used to take off when you put your foot down?
When it was getting the work done and the MOT,  I noticed that it was running very rich, showing up on the meter, the mechanic fiddled with a little screwdriver to lean off the idle, I think?

Update–
I cleaned up the contacts on the oil pump and oil light no longer lights up on start up
The engine started first turn this morning and sounded good,
Took it for 80 mile trip and it still feels sluggish, something is not quite right?? I noticed two things, 1- it 'pinks' a lot up hills and 2- its smells rich on idle???
I'm confused, anyone have any ideas? Thanks

If it's "pinking" up hills the timing is out and that is why it's sluggish.

Dont touch the mixture yet, you need to get the timing done but make sure all the electrical stuff like HT leads etc are in tip top condition then timing, then mixture and idle speed.

oh yes, new air filter or invest in a K&N panel filter which looks like the paper one but lasts years and will pay for it self over time before touching the mixture as a dirty air filter will affect the mixture.

Thanks,
will get timing checked next.
it has a new filter in, I'm sure it was Foam type, but have another check and look.
The idle was just under 1000 rpm, the is a little white line on rev counter, it was on that.
I think I will try a new dizzy cap by beru, just to see what happens?

950 to 1000 rpm is where it need to be, I run mine at 1000 rpm as mine seems happier and less rattles at that speed.

Help again - I was checking the part numbers for both the rotor arm and dizzy cap tonight and thought I would just check, again, the HT leads. When I checked the connection to the coil the rubber boot connector was a bit loose, I pushed it in and it popped back out? I adjusted the copper circular inner connection and pushed it back on, and it popped off again? it just wont stay in place. Eh?
Could this be the source of my troubles? I am going to replace the leads now that I think this may be  a problem, was going to get Bosch or Beru, but I cant find either on the web. Anyone know where I can obtain?
thanks

There is 2 types of connections on the ht leads, dissy cap and coil, which type do you have?

There's later type with a pin in the middle and the early type with no pin, they look the same on the outside but have a different way to connect the leads.
If photobucket was not being a pain I could post up a picture..found an old post, hopefully you can see the pictures?
https://vwgolfmk1.org.uk/forum/index.php?page=topicview&id=big-block-carb-engines_2%2Fdizzy-cap

Have the earlier type, no pin. I found the old leads which appear to be Beru and fitted the one from dizzy to coil, what a nice fit, however, suspect that due to age this will need to be replaced, they may be original. Did notice that either end is different? Do you think that the bad fit of lead to coil may be my source of trouble? Poor spark maybe?
Anyways now on the hunt for new leads, any ideas?
thanks.

So do you have no pin on the coil connection, no pin on the dissy cap?

Spark plug ends do not really matter as you can unscrew the cap or screw the cap back on depending on what's on the end of the lead.

Could be your problem of a poor connection making a weak spark.

Found this set on eBay, they are for cars with no pin on coil and dissy cap, spark plugs you need to unscrew the cap so the thread is showing on the end.

http://www.ebay.co.uk/itm/VW-GOLF-Mk1-Mk2-HT-Leads-Ignition-Cables-Set-74-to-84-Bosch-171998031B-Quality-/232465561163?fits=Model%3AGolf&hash=item362006f64b:g:u24AAOSw-81ZolPG
 

Yes no pins at either. Checked the original set and 3 were Beru and one Bosch, no idea what the current fitted ones are.
Came across a Beru set Ref: 0300890432 which appear to be the ones?
Yes the link that you sent also seem to be them, which are the better ones to go for, I suspect they are both more or less the same?

I bought the Bosch set I posted the link to which are fitted to my Mk1 scirocco,  I could not find a Bosch dissy cap so went for a Beru cap and Beru rotor arm.
They have been on the car for about 9 months and have been working fine together.

New Bosch dizzy cap and rotor arm arrived today, found them on Ebay, genuine products. waiting for HT leads and fingers crossed things improve. At least these parts will be eliminated.

Sounds like a good plan.  I change my HT leads, etc every 2 years or 20,000 miles in my golf as it's my daily and I need it for work.

I did leave it for 5 years before changing the leads on my Mk1 Scirocco and I did notice the difference in starting and driving the car.

Update/progress;
Have fitted the genuine Bosch rotor arm and dizzy cap, (found them on Ebay) and eventually the HT leads arrived from Germany, took ages to get here, Beru, which match the fitted originals that I still had in the cupboard. Just taken the car for run and the pinking seems to have gone!!  
When I started the engine today, from cold, the engine kept dying when I pressed the accelerator, once warmed it had a lumpy idle but revved. It still seems to be rich? My next plan is to get the timing checked and maybe the mixture? Any thoughts as to next step?
Thanks

how long was it stood for? have you changed your fuel filter? when you say running rich what was the co reading on the mot? should be around 1.8%. sounds like fuel issue to me

first thing I would do is change the fuel filter and if no better do an injector test to see if they are spraying, you could try putting some injector cleaner in first.

if all that is ok then I would get the co % checked at a garage to see what its running at, it is adjusted with a 3mm allen key in the hole in the metering head