T25 misfire misery

[gardengirl]

Hi everyone
Ive read through loads of threads but am at wits end with my beloved 1983 watercooled T25 1.9 petrol. It sat all winter away from home with nearly empty fuel tank, have had him back two months and had intermittent misfire and loss of power problem ever since. So far I have changed dizzy cap, plugs, air filter, rotor arm, fuel line and fuel filters. carb has been taken out and cleaned twice. Been to two mechanics, each time carb was cleaned and van ran ok briefly then problem started again. Seems to be no pattern to problem can occur any time, always after auto choke comes off though. Doesn't matter what speed i am at starts to lose power, misfire then engine dies. Have to pull over and restart, usually starts again straight away and is fine for a few miles till happens again. Could fuel tank be full of muck thats getting sucked up after winter? Be grateful if anyone can recommend local mechanic who knows their vans, Im in Shrewsbury area and losing faith in mechanics Ive already used as well as losing lots of money replacing parts that aren't fixing problem.
Thanks!

Sorry....forgot to introduce myself as im new...how rude!

My name is lisa, im from shrewsbury and been proud owner of Earl for five years. He's a 1.9 petrol T25 Westfalia high top conversion and came to me in a pretty sad state after sitting in a field for two years. He now looks much more handsome after nearly a years hard work tidying him up but this misfire and cutting out problem is getting me down and im losing confidence in taking him far from home in case we don't make it back, with two kids and a dog in tow sitting on hard shoulder waiting for rescue not much fun!

[kevtherev]

Hello Lisa welcome to the forum
misfire after the choke comes off is a weak mixture.
This could be caused by an air leak on the inlet side or poor mixture set up.

Usual air leak suspects are...
vacuum lines perished or missing
gasket(s) split
brake servo hose perished.
Choke pull down unit failed

usual mixture issues are
fuel pump faulty
fuel pump pushrod worn out
too many filters in the fuel line (and clogged up)
fuel filter in the carb clogged (not a well known one to mechanics)


The Club has a camping area at Deva Dubs & Rods (Shrewsbury show ground) this weekend.
I can't guarantee it but there will be a lot of knowledgeable members there who might take a look

[gardengirl]

Thanks very much, will try and get over this weekend.

[Ralf85]

Hi Lisa. If the motor was working fine before, then my money is on a filter blockage somewhere. It sounds like when you filled the tank it stirred up some muck. That happened to me. In my previous van, I had the insulation crack on the top of the rotor arm which also caused a misfire, but you have replaced that. Kevtherev has pointed you in the right direction I reckon. Good luck.

Patrick

[gardengirl]

Thanks Patrick.
Have got him booked in somewhere local that specialise in VW restoration, said theyd take a look. Dont feel confident trying to sort anything else myself.....more a gardener than a mechanic! Hoping they can put the old boy right and I can make meet at shrews this weekend. Will let you know how I get on.

[kevtherev]

Print off the replies you have and ask them if they have checked out the mentioned ones.
you knowing stuff will mean they will be less inclined to be vague with you

[gardengirl]

Thanks Kevtherev, thats exactly what ive done, wish me luck!

[gardengirl]

Hey everyone
Hope all of you who made it to Shrewsbury had a great time and didnt get too soaked on Sunday. Anyway, much as i'd have loved to join you my poorly old boy didn't even get me home from the garage! They had a good look and said they couldn't see anything specifically wrong, tightened some bits and bobs and hoped that would sort my problems. Half a mile down the road I started to lose power, misfired and kangarood my way back home feeling very sorry for myself.So....I'm back to square one with a van I cant take anywhere and desperate for some advice on where I go from here. Could it be ignition amplifier module problem, that seems to crop up regularly as causing this type of problem, only thing is I can usually start him up straight away after stalling, don't have to wait. Be glad for any ideas or any recommendations of knowledgable garage close by....not brave enough to try to drive him too far now.

Thanks.

[Ian Hulley]

Have you put some fresh petrol in ? Old unleaded goes stale, a change of fuel filter and some fresh fuel may help .... if it wasn't broken when it was parked up there can't be that much different now. Another example of why running these vans is better for them than being parked up.

Ian.

[gardengirl]

Hi Ian
Yes he had fresh fuel, plenty of it , have driven him around quite a bit regardless of problem taking him to one garage or another. Had new fuel filters, dizzy cap, rotor arm, plugs and air filter, also had carb off twice to be cleaned. Nothing making any difference. Last place I took him thought it could be electrical problem but couldn't see anything obvious. Just looked at ignition amplifier module and looks like someone has recently had it off and scraped at back of plate Im assuming to ensure connection? He was only sat around as he was having bodywork done and awful winter weather meant he stood much longer than i'd have liked. So Im stumped now as to whether its a fuel issue or electrical, no obvious air leaks according to last garage who checked him out.
lisa

[Ian Hulley]

What about the tiny filter on the carb where the hose goes in ?

Ian

[gardengirl]

I dont think there's one on there....if there should be maybe thats my problem?
Lisa

[Ian Hulley]

If it has a Pierburg on it then there's the tiny cone filter set into the carb on the inlet, If it's a DG then it SHOULD have a Pierburg.

Ian

[kevtherev]

If it's a pierburg carb.... and most of them are then it will have one... see the wiki to remove it

[icosahedron]

Considering everything that has been tried, I would turn my attention to the ignition amplifier. Thermal expansion and contraction eventually weaken the joints between the electronic components leading to intermittant connections. Very little electronics on a DG and replacement would give peace of mind even if it does not solve the problem.