T25 1988 1.9 auto choke problem

[gorgeous george]

Hi
I have a 1988 1.9 petrol water cooled T25 DG engine.
I purchased last June and straight away had a problem with the press accelerator down once auto choke method.
It does start, However it really struggles to idle, but if you press lightly on accelerator for couple of minutes once
warm it's Ok.

Also I put camper up for winter from November to March. Once spring arrived I took it to my local Tyre & exhaust center
to have a new stainless steel exhaust fitted ( purchased from just kampers, Not cheap!!)
Prior to this I had fitted new plugs, leads, distributor cap.

When I collected the van expecting it to run lovely ( How wrong I was.!!) It coughed and spluttered and hesitated on acceleration.

I tried to basically give it a good clear out on the dual carriageway thinking this would sort it out as it had been standing for a while.
I put new fuel in as i was informed that fuel can go off?? but no difference.

When I inspected the exhaust it seemed to be blowing slightly from the joints. I put some fresh exhaust paste on joints, tightened all
joining bolts including manifold joints.
This seems to have made some improvement but not solved the issue completely.??

I am new to the vw scene and could do with some advice.
Many Thanks

[SILVERFOX2013]

hi m8 choke flap its in the top of carb regulates air make mixture rich so as engine can warm up to check its working
remove air filter run engine and it should start to open fully open after approx 3 / 5 min of runing if not its the auto choke 12v element loads avalible not expensive easy to fit . best read up and do some investigating as for exaust engines need back presure at corect amount change exaust & its recomended to retune engine ie carb and igntion timeing any holes leakes need fixing

[itchyfeet]

Sounds like a broken choke flap to me as I had the same
Whip the trunking off and see if its free to move if so its the plastic link broken deep inside the carb

[pionte]

It wont be all of your problem but... if you had a new exhaust fitted by a garage and it leaks, then take it back !! a new SS exhaust should be perfect, if its not perfect now then it will only get worse. You should not have to be trying to seal it yourself.

There is loads of info on here all about the Pierburg 2e carburettor and the issues that they all have if not set up correctly, it is critical that you have no vacuum leaks , so check all the pipes, carb to distributor, carb to pulldown unit, carb to brake servo. Then as others said , check your auto choke operation..

[kevtherev]

First post and it's a shame you didn't come here first before spending money..
take it back is the first advice..
Then never darken the step of another "exhaust centre" you need mechanics to fit these exhausts not monkeys that just fit things, without thought.
Secondly assuming you'll be doing this yourself...IF the choke is working correctly as pointed out, then the fast idle on the cold start may need some adjustment.
This is done with the autochoke housing, it can be rotated to keep the fast idle on longer.
BUT
Before you do adjust it liberally oil the mechanism as they do seize up.

[gorgeous george]

Thanks so much for all the advice. Will take a look at all the mentioned possible problems and post back!!
Should have come here in the first instance.!!

[gorgeous george]

So Removed the air filter today. Removed the carb top plastic cover and basically the choke flap is not
broken as I manually closed it by hand and It sprang back open.

However on cold start using the auto choke press accelerator down once method, The choke flap
does not actually close at any point, and as I understand it should start off in the closed position slowly opening
as engine warms up!!

Whilst engine running If I close it slightly by hand the revs pick up, let it go open again and it struggles to tick over.??

Anyone got any ideas please as it would be much appreciated.!!

[kevtherev]

It's far too mild to be completely closed
The choke is operated by a bi-metal spring.
The spring unwinds as it heats up.
you can see the adjustment aswell here



The choke flap is one half of the warm up mechanism
the other half is the fast idle that works with the choke
it uses a stepped cam to regulate the idle speed
here it is on it's highest setting (2000 rpm)



here you can see the operating springs



all this can be adjusted
but basically when you step on the acc before starting the cam should flick round to it's highest setting, and will stay there untill you touch the throttle where upon it steps down to match the choke position
as you can see mine is well oiled, clean and free to rotate

[gorgeous george]

Thanks so much for the advice, and the pics to help me understand better.!

I will take another look over weekend and let you know how I get on.
Thanks Again!!