Running issues!

[Johno4048]

Hi,  I have a Mk2 Golf GTi 8v Digifant.  Several months ago I took it off the road to replace the exhaust manifold and do the gaskets at the same time.  I started stripping the top end off and then had to go away for work.  I got back and put the engine back together a few weeks ago and it will not run.  It turns over goes up to 800RPM, instantly drops to 500 and stays there until it cuts out usually after 20-30 seconds.  Looking at the engine it seems to be slowing and certain points and then will slow to a stall.  If I depress the accelerator it cuts out immediately.  I used start pilot the other day and it ran much better, I could accelerate as long as I was spraying the start pilot, as soon as I stopped the engine cut out.  This leads me to believe it is a fueling issue?

So far I have;
Confirmed the lift pump is working and checked the lift pump filter
Checked the main pump
Cleaned all earths
Confirmed fuel is getting to the rail and continues to pump on ignition
Confirmed timing as per RubJonnys guide, I have checked again since doing it
I am getting spark to all four plugs
Checked the wiring to the fusebox

I have Replaced;
The pump fuse and relay
Distributor
HT Leads
Spark plugs
Coil
rotor arm
Replaced all vac lines around the inlet manifold

I have noticed that one fuel injector has a slightly mis-shaped seal, I am waiting for a replacement but could this be preventing it from running by allowing air in?  I will also be receiving a new blue temp sensor in the post over the next couple of days.

I'm running out of ideas now, if you can think of things I've missed please let me know.

[gazareth]

how much of the engine did you dismantle?

[Johno4048]

Not much -  just removed the cylinder head, and exhaust manifold.  New gaskets and I removed the starter motor to clean it up. 

[gazareth]

ah you had the head of it. well I would start by going round the engine checking for loose wires or split hoses first. they can be damaged easily on removal. did you have injector rail out?

[Johno4048]

I have checked hosing.  I did take the fuel rail off and I am concerned I may have damaged a cable.  The wife has 'tidied' my multimeter and I can't find it to test the plugs properly.

[Brighouse-gti]

Have you tried adjusting the fuel/air mixture? Also try cleaning out the ISV.

[gazareth]

tidied as in put away in a safe place. so safe no one will ever find it again . if the engine revs fine with the spray then it sure sounds like a fueling or intake issue. are the hoses to the fuel rail on the right way? another thing to try is get the engine running on the spray,get the revs right up then stop the spray and see if engine keeps revving or cuts out.

[Johno4048]

Yeah exactly that, though I found it today - in a carrier bag with some old kids toys.  The feed and return pipe are on correctly.  Tomorrow I will try running on the spray as you have suggested and I will check the electrics at the rail and plugs.  If it cuts out as soon as I stop spraying or slowly dies will either indicate more clearly towards a certain issue?

[gazareth]

you mentioned the fuel pump stays running with the ignition on? it should only run for a second or two when you switch ignition on then run constantly when engine is started.

[Johno4048]

Yeah sorry that's what I meant.  I turns off after a couple of seconds but runs once the engine is running.