mk 2 gti 1.8 8v k-jet running very rough help

[scott123]

hi I have recently bought a mk2 1985 model fitted with k-jet engine its running very rough on the first stage on the throttle... want idle ,stalls etc but revs up on the second stage.
when I remove plug leads from cylinder 1 and 2 the engine doesn't change so its only running on 2 cylinders.
 Up to yet I have re sealed and checked injectors , swapped the metering head, tried 2 different distributers ,new plug leads, new plugs with good spark, changed cold start injector , checked for air leaks ,compression tested each cylinder which was all good and checked timing ,

has anbody got any ideas what it could be or what eles to check ?

thanks scott

[gazareth]

so you have narrowed it down to a problem with cylinders 1 and 2. could be bad valve stem oil seals letting oil down to plugs. pull the plugs out of 1 and 2 and check them for oil fouling. would also check camshaft for worn lobes or broken valve springs. does it run well at all? like when its cold or warm. or does it run rough all the time?

[scott123]

plugs clean getting fuel just a little choked up but clear on high revs and seems to run ok after about 3000rpm , also checked cam, seems fine.   yes runs rough all the time

[gazareth]

does it smoke much from tailpipe?

[scott123]

no doesn't smoke

[gazareth]

if its getting fuel but no spark then the plugs would be wet with petrol. try changing plugs 1 and 2 with 3 and 4 and see what happens. also check plug gaps if they are single earth electrode.

[scott123]

the plugs are 3 point I have swapped them around to make sure they arnt dudds, even tried new plug leads  to make sure its not them

[gazareth]

ok try swapping injectors 1 and 2 with 3 and 4 and see what happens. btw is your engine solid or hydraulic cam followers? and also what are your compression readings?

[scott123]

its had 4 good injectors out of a spare engine put it and it just the same its hydraulic cam followers and compression readings were all around 200psi

[Diamond Hell]

You're going to need to go round and pressure-test the fuel system and ensure the warm up regulator is doing what it should be.