Intermittent Problem

[Maccas]

Hi,
Hoping someone might be able to help me with my rocco. It's a 1989 mkII.

The problem:
The car will be running fine when suddenly it looses power and starts running very rough - kangarooing erratically.
As soon as I dip the clutch or put the car into neutral - it idles perfectly.
When the problem occurs - I've found pulling the choke out helps - it still runs roughly but giving it some choke enables me to keep going + make it up hills!
If you turn the engine off and leave it for 5 minutes - the problem often goes away (if only for a while).
This has been happening for the last week or so. Some journeys the car will run fine - then other times it will be terrible!
I experienced the exact same problem about 6 months ago - it lasted for a couple of weeks then completely disappeared ...until now!
At the time I was advised it could be rust/muck in the fuel.
I had a look in the tank (took off the sender unit under the back seat) - but the tank & fuel looked clean as a whistle.
Dropped a magnet in - but didn't get any bits of rust out at all.

Any suggestions/ideas welcomed.
Please bear in mind I'm no mechanic - so will need simple jargon free advice!
Many thanks,
Maccas

[monzajake]

First off i take it yours is a carb model ?

Have you checked the rubber mounting plate the carb sits on ? located between the base of carb and the inlet manifold.
Remove the carb and inspect it for wear n tear. Pretty simple job.
If your still running the standard carb *pierburg* then it may either need a dam good set up and overhaul. It could also be what i know as icing up. If i remember right its were the secound choke dosent pull down fully cousing a fuel shortage.

Or it could be quite simple as in some thing like one of the vacume hose's running to the carb or on the carb for the pull down unit for the secound choke..

[Maccas]

Yep, It IS a carb model.
As far as I know it's the standard carb.
Is there an easy way to identify whether it is a Pierburg?
...if it is - should I consider replacing it? Is it right that they are often temperamental.

Cheers for the suggestions.
I'll attempt to check the mounting plate for wear.
Sounds like I'll need to get someone who knows what they're doing to have a look at my carb!

[Jay4424]

it'll say on it somewhere what it is... 2E2 pierburg of something, the replacement is a Weber 32/34 DMTL (from memory... do check though... http://www.webcon.co.uk/ and go to the "direct replacment" page)

you can check the mounting rubber as it stands, just look, poke and move the carb (you'll see crack open up if they're there!

Just athough, have you checked the fuel filter where the fuel pipe enters the engine bay (back left hand sied as your looking into the engine bay, may be dirty, may want to replace anyway!

the fuel conseritor may also be breaking up internally.. I've never been inside so can't help there, if you can even get insidem I may be talking rubbish there!

vac hoses do check all, including the one behind the carb, check the cable to the heater (little black cylinder looking thing, I forget where it is on the standard carb, on the weber its at the front... it has one cable to it, and uses the body as earth... check the earth! if you have a meter, or light bulb tester (a bulb with two wires attached) check the supply to the heater.

can't think of anything else atm.

Jay.

[Nate]

if choking it improves the problem, it's got to be fuel starvation. check the condition of the pipe to the fuel tank from the filler cap.

the fuel conseritor may also be breaking up internally

???

[Jay4424]

fuel conseritor... it bolts on to the front of the engine at teh rocker cover, it has three pipes, i thought it was to regulat the amount of fuel from the pump to the carb, and returning the excess to the tank?

[Nate]

ah! yes, i know what you're on about, but never heard it called that before. always called it a swirl pot

[Maccas]

Cheers for the all the suggestions.

The carburettor, vac hoses etc seem to be fine.
The fuel filter was pretty dirty though, so I changed that.
The car ran well for a day or 2 after - but now it's as it was before ...intermitantly terrible!
On inspecting the new fuel filter, I see there are a few grains of dirt/rust in it.
So I'm thinking the problem IS a rusty fuel filler neck causing fuel starvation.

I understand that NO new filler necks are available
So, where do I go from here?
I'd be gutted to have to get rid of the car because of this!
Where could I look to get a good second hand one?
Alternatively, has anyone ever looked to get one made??
...just thinking I work on an industrial estate and am surrounded by metal shops that could probably sort me out! ...any pitfalls in doing this?
Or am I better to modify an existing filler neck? ...If so what? One off a Golf?

Many thanks for you help guys.

[LEEP]

pm markh he did one from a bmw and also you could modify a golf mk1 as well or take or old one of and see if its worth welding up then give it a coat of meatal ready and then a coat of por-15 rust proof paint job sorted then mate

[Ian Carvell]

The filler neck wont be the cause of the problem, but if there is crap coming from a corroded filler neck then that will cause problems if its getting into the carb.

Clean the jets out in the carb and fit an inline filter into the fuel supply hose to the fuel pump.

Pierburgs are prone to blocking up the jets...my Scalia did it twice, but if you are pulling out a choke I guess it must be a webber DTML?

[whatalotafun]

try draining the tank, sounds like you may have got some water in there, this sounds like the problem to me. may have got in via a hole in your filler neck!

if you can drain the contents into a clear bucket you would soon tell if there was water in there too.

[Jay4424]

I have a filler neck going.. you'll need to come and get it off teh trailer though.. you can help me remove the entire fuel tank at the same time

...you have removed the lifter/fuel level sensor to check the intake mesh right? ..you'll get a good look in your tank at the same time (you'll see debri/or not!)