K Jet - Injectors not squirting after head removal

[Wayne]

To manually lift the metering flap, use something to grip the center nut on he plate but be carefull

[bodga]

I recently brought a F reg gti 16v mk2 of this bloke, it has been sat on his drive for @ 10 years due to his health problems. Anyway one of the problems i had with it i sorted last nite. she was constantly flooding and missfiring. The air meter flap was very hard to pull up and then become loose. , All i did was remove the distributer from the air box, The needle in the center under the fuel disributer was very stiff in its seals, i carefully pulled the needle out with a pair of pliers with its jaws wrapped with rag so i didnt mark it, cleaned it with petrol. (it should be spring loaded and push in and out quite free. boy is she running sweet now! it seems like you have a similar problem. good luck

[bmouthboyo]

OK bit of an update:

I went and manually lifted the pressure plate and a tiny amount of fuel seemed to trickle through and injector i had removed.

I think the fuel filter is old and when I undid it to remove it a lot of yelloish fuel came out, albeit the reverse of the filter so i guess expected.

What I dont understand is there is lots of pressure and fuel coming from the cold start line, but nothing from the injectors. Could the piston thing on the fuel control valve be blocked? Any way of cleanign them or is it a new air flow distributor job?

If so anyone know where I can get one?

Thanks

[Diamond Hell]

You've disturbed an elderly metering head from it's nest.  It's going to be upset. 

It will probably now be well out on where it should be, so chance is you'll need to work on re-calibrating it, which is going to be a complete and utter ball-ache.

Quite seriously, this is one of the biggest things about K-jet that put me off ever bothering with it again.  I've been in so many situations where the metering head's been out of the vehicle, not much has happened, it's gone back in and been shot away.  I suspect it needs adjusting to sort it so something actually happens when the flap is lifted.  At the moment it's probably way off the bottom of the scale.  You'll need an absurdly long allen key to adjust it up in to range.

If it were me I'd be off looking for a dead car with a good Digifant injection system on it - it'll take away a lot of these problems.  Finding another (good) metering head will be a bloody nightmare, too.  Have a look at replacement prices, just make sure the jaw-catching tray is in place before you start looking.

[rubjonny]

the cold start line doesnt need as much pressure as the main injectors as it is electrical, plus its on a different part of the metering head as the main injectors. the 5th injector just gets a steady supply of fuel whereas the main injectors have a varying supply based on the engine load.

[bmouthboyo]

You've disturbed an elderly metering head from it's nest.  It's going to be upset. 

It will probably now be well out on where it should be, so chance is you'll need to work on re-calibrating it, which is going to be a complete and utter ball-ache.

Quite seriously, this is one of the biggest things about K-jet that put me off ever bothering with it again.  I've been in so many situations where the metering head's been out of the vehicle, not much has happened, it's gone back in and been shot away.  I suspect it needs adjusting to sort it so something actually happens when the flap is lifted.  At the moment it's probably way off the bottom of the scale.  You'll need an absurdly long allen key to adjust it up in to range.

If it were me I'd be off looking for a dead car with a good Digifant injection system on it - it'll take away a lot of these problems.  Finding another (good) metering head will be a bloody nightmare, too.  Have a look at replacement prices, just make sure the jaw-catching tray is in place before you start looking.

ouch lol

What is puzzling me is it wasnt removed from the head, just left as it was whilst I sorted the head and manifold out (thanks btw), im looking for a replacment and in meen time replacing the filter and having a little tinker. Fingers Crossed

[bmouthboyo]

OK bit of an update.

Today i replaced the fuel filter and put the metering head back on after trying to clean it out as best i could, the piston moves freely and i blew down the main hole and seemed to push some crud out of the holes that lead to the injection lines.

Poped it all back together, the injectors seem to be working (although not perfectly as sometimes one doesnt seem to want to squirt. I swapped the working and non working injectors around and still same lines not working. It seems that some times there just isnt the pressure to work the injectors on a certain line.

I have a feeling that the metering head is still at fault and possibly gunked up a bit still. I have 2 replacments on the way so will try them and see.

On a side note, i tried to start the car when all 4 injectors seemed to be working, but when its tcranking there does not seem to be enough suction on the air intake to lift the plate to deliver fuel, I removed an injector and whilst cranking nothing came out, however when i manually lifted the metering flap fuel comes out. Could this be a simple leak in the piping somewhere preventing there from being enough suction to lift the plate during the crank? The plate moves up freely but i wouldnt describe it as "no resistance at all" as when the pumps working it is a tad harder to lift.

Any comments appreciatd, ill keep you updated.

[rubjonny]

if 1 injector isnt spraying and the problem remains when swapping an injector over id say your metering head has crap in it, and now its basically scrap. 1st thing on the list is a new fuel filter, and before you fit the new metering head put the main feed pipe into a container and prime the pump a couple of times to ensure there is no crud in the system.  you'll want to blow out all the bay fuel lines to make sure theres nothing lurking there, and ideally replace the wur as this could have crap inside too. I've seen guides on opening them up to clean out the insides but not sure that would end well.

2nd hand mheads are a risk too, have to hope that whoever stripped it off did it properly and stored it carefully so as not to let anything get inside