8 valve engine won't start

My 8v GTI digifant seized up a while ago so I bought another engine from a friend that had stood on a pallet in his garden - covered up - for about a year. I have installed the engine into the car and cannot get it to start.

I have checked earths etc. have fuel into the cylinders, have a good spark, timing seems okay, and it was a runner before it came out of the previous car, but it won't go.

The fuel pump works, I've swapped the ECU for the one that came with the engine, everything else seems to be okay. The compression is 7.2 bar on all cylinders except 4 which has 6.5. All contacts on sensors are clean.

Any ideas what I might do next, please.

 

check all wiring and sensors (crank, temp)

 

How long has your car been off the road? I'd start by testing that both fuel pumps are working.

Did you change the dizzy, or are you using one that came with the engine?

 

This engine has been off the road for about a year. Today I set up the engine timing, put the distributor in the correct place - it wasn't before - and got it to fire but it won't run. It fires, turns over for a couple of seconds and then stops.

Seems like it isn't getting sufficient fuel to run. The tank was almost empty so I put a couple of gallons in (9 litres) but no difference. The car is a 1990 8v GTI. Do all MK2's have two fuel pumps as I thought the later ones had only one.

I did wonder if the engine would run without the exhaust connected but can't think of any reason that it should although I would expect it to run rough.

 

Whoops I forgot. The pump definitely primes when the ignition is switched on, it runs for a couple of seconds and then stops.

 

I had this sort of issue when I done my 2.0L conversion. I didnt tighten the inlet manifold bolts to the head properly so it was sucking in too much air and stalling. yours could be something else but worth checking as I know the inlet bolts can be awkward to get to.

 

This engine came with the inlet and exhaust manifolds on it but I hadn't thought of checking the bolts. I'm pretty sure that it came out of the previous car in one lump and had been running previously. I will check them though.

 

when I did have the issue I could keep the engine running if I kept the revs up but it wouldnt idle on its own. maybe check for other airleaks too. Double triple check timing too, very easy to overlook. Remember timing mark on the cam pulley is on the inside face (the one closest to the head)

 

Yes, thanks, I know where the timing marks are and have set up the basic timing which I'm sure is correct now. I can't finally set the ignition timing till I get it to run.

Anybody know whether the compression would be a factor as it's pretty much on the lower limit at 7.4 bar. Might this improve when the rings start moving again?

 

Update. I went over the ignition timing and with some easystart got it to fire up. It now fires up but won't run.

I think it's either a fuel pump, or the crank sensor. When I asked my son about the crank sensor he said that when he was putting the wiring back he managed to pull both the connectors off the oil temp sender and the cranshaft sensor. He thinks he might have swapped them round!

Anyone know which colour wire is which?

 

I dont think its possible to swap the wires over from the crank sensor and the oil temp sender. Also I think it may still run with the knock sensor unplugged (I think)

 

Then what is the sensor just to the left and behind the dizzy? Don't know if the rev counter is working but I will check later.

Thanks for the advice.

 

I just assumed crank sensor was another word for Knock sensor

 

ive had a similar thing turned out to be the intank pump pull it out and make sure its working you can hear the main pump but my money is on the intank pump not working