Golf MK1 GTi just won't fire up!

Hi!

My first post

So, been trying to get my golf GTi to fire up since changing the piston rings. It hardly worked well before doing it, so don't think I have made it worse. I was getting low compression of between 50 and 75 psi. After renewing them poison rings, it's up to about 100 for each cylinder (I know this is still low)

Things that I have checked:
Compression - around 100 psi in each cylinder
Fuel injectors spray out fuel in roughly equal measures
All 4 spark plugs getting a spark
Fuel pump primes when ignition is turned
Starter motor turns over
Battery is full

Tried to jump the starter motor directly and get the same thing (keeps trying to turns over)

But just doesn't fire up!!

Any suggestions?

Thanks

Have you checked the plugs are sparking in the right order. perhaps you have inadvertently swapped a couple of plug leads. Is the timing correct? 

Thanks golfy1. Last night I was trying again, and as I was jumping the starter, I twisted the dizzy anti-clockwise, which just about got it fired up for a few seconds

So think you are right, the timing is off.

Now to work on that today!

Cheers

Quite an easy mistake to put the dizzy on 180 out. Double check that. Did it with mine after a full rebuild and did the same as you, spent ages chasing other things!

Also check the timing belt marks

https://www.cabby-info.com/files/ignition/AdjustingTheTiming.pdf

set the static marks as


For the DiZ.  Slacky  the timing belt so you can spin the Diz.

When setting the diz, spin the intermediate shaft to align the rotor to the hash mark stamped in the Diz housing.
That is the number one wire.  1-3-2-4

Do not worry about pulley marks or what nots.  IF the Crank is a 0 by the tranny finger the (0) not the Diamond.
and the Cam dimple is even with the valve cover tin not the re-enforcement bar.  That is when you spin the Diz to 0, and reset the tension on the timing belt making sure that the marks don't move.

out of the 50 or so timings that I have done on my Cabriolets this is how I dude it.

As I have a plethora of 90 Digifants, I stopped using a timing light and set it with a DVOM easier you don't have to mess with any thing.  It is in the link for those interested.