MK1 GTI Cabby wont run

Hi all,

ive changed the brakes on my mk1 which is great, they work again! however after driving it up the drive i came to use it an hour or so later and i cant get it to fire. Im geting a good spark (cleaned the plugs, rotor, cap leads etc) and the plugs are getting wet so fuel is getting through but it wont run at all and only occansionally coughs and splutters. its a real head stratcher so any suggestions welcome.

Cheers

hi again,

im thinking it could be the injectors, i dont really know alot about injectors though or how they work. I'm worried that i might have damaged something while blowing them out with a air gun although it has ran (drove up my drive) since then….

Thanks

Better do an injector test then

http://www.vwgolfmk1.co.uk/Main/Testinjectors.pdf

Cheers…………….

thats awesome, cheers mate.

Ok this is strange, i had injector one out with my thumb over the end and the spark plug and the engine ran on three.. ive put them back in and it wont fire..

cabriochris said

hi again,

im thinking it could be the injectors, i dont really know alot about injectors though or how they work. I'm worried that i might have damaged something while blowing them out with a air gun although it has ran (drove up my drive) since then….

Thanks

Unlikely to have damaged them if the car still (sort of) runs, but its certainly possible you've dislodged some dirt, which means they now open more easily or something, and thus the mixture is now wrong. So checking the mixture would be a sensible idea.

tried the test, i disconnected the wiring for the 5th injector but still seem to be getting alot of fuel out there and dont seem to be getting any out of the injectors.. any advise?? im having a look in the black head thing and going to lookin the lines..

cheers

You're getting some pressure but not enough. Also your 5th injector is leaking, so it needs to be swapped with a good one. Next step - check all fuel lines to check for any kinks, its possible you have a kink somewhere (possibly before the fuel pump) which would cause low pressure. Once you've eliminated this, you're into either swapping out the metering head and/or WUR and/or fuel pump with known working ones; or connecting a fuel pressure gauge to pinpoint more accurately what's going wrong.

the fuel is firing out the 5th injector with quite alot of pressure though.. i'll check the lines now around the pump. the pump seemed to be working fire before but i'll have a look at all the that.. thanks

errr :?  ive just realised i migth have droped a huge clanger. on the black fuel distributor thingy (technical name) theres 4 alan key blots with 4 more under it.. i've kind of taken them out before the last post because i thought there was a blockage in there… i've just looked in haynes and it says do not remove! are they like jets are something??

cheers

sorry to sound stupid but whats the WUR? the garage i took the car to cant pin point the problem because they dont have the pressure guage tools… are these easy to come by?? and how do i check? when i checked the filter there seemed to be sufficient fuel pressure passing through..

Thanks

WUR is the Warm Up Regulator - attached the front of the engine block next to the distributor with two fuel lines running form the metering head. A good post here on problems with one and testing it…. http://www.vwgolfmk1.org.uk/modules.php?name=Forums&file=viewtopic&t=908

Cheers

thanks for that, its ace.. im having another look today… in the rain!! on the air filter box i have a black cone thing with electrical connections (dont know what it is) but it was a yellow vaccum like line coming out of it but isnt connect to anything?? where should it go? i've had a look on the inlet but cant see any loose..

cheers

the black cone thing i believe to be a diaphram switch or something but still cant see where it goes..

okie doke, i've taken of the pipe that goes on to the 5th injector and the cars running fine.. but i cant stop the fuel flooding out on the 5th injector pipe..   i've disconnected the blue electrical connector that is positioned just underneath and this has made no difference… all suggestons welcome..

thanks

ps i still havent found where that yellow vaccum pipe goes.

paul_c said

You're getting some pressure but not enough. Also your 5th injector is leaking, so it needs to be swapped with a good one. Next step - check all fuel lines to check for any kinks, its possible you have a kink somewhere (possibly before the fuel pump) which would cause low pressure. Once you've eliminated this, you're into either swapping out the metering head and/or WUR and/or fuel pump with known working ones; or connecting a fuel pressure gauge to pinpoint more accurately what's going wrong.

sorry mate i dont follow.. is the injector in the inlet?? if so i havent had it out… i only took out the banjo bolt out of the end of what i thought to be the injector and put the pipe in a jar. the fuel is flooding out as well and doesnt seem to stop..

thanks again

Yes, the fifth injector is screwed into the end of the inlet manifold with two allen key bolts, you've just removed the fuel line to it. Try testing the fifth injector itself, it should only emit fuel for ten or so seconds when firing from cold. Have a look at this site Domain parking page which explains how K-jet works and it's components.

Also the four allen key covers you removed from the black fuel metering head cover adjusters for fuel pressure to each fuel line. Assume you have you put these back in?

Good Luck

thanks for all your help. i've replaced the metering head and removed the fifth injector and its running.. i have a new injector on order. The car just about idles ok but cuts out at junctions etc and has a slight missfire.. can i assume this is the mixture??

How on earth is it running with a missing 5th injector???