3b not running on all cylinders?

[Tomhorner]

Evening, sorry for not posting much before I have been busy with my s2 and wanted to have her back on the road before I done a full write up which I will do at a later date, anyway I have had the engine and gearbox out had the head off the engine as a couple of the water manifold studs had sheared, once these were sorted I taken the sump off the engine cleaned all the block painted it, had all the parts sump, inlet manifold ect all powder coated and refitted them all with new gaskets and put a new cambelt, idler and water pump on off Pete at Quattro parts who I have spent nearly 2k with! :/ I've now got the engine in, but have left the power steering pump off until it's all running okay I've got all coolants ect in but the engine is only running on two cylinders?? It's hard starting and then only fires on two and runs very Rough as you can imagine.. Can anyone help me?? The cambelt timing is spot on with the cam and the distributer timing appears to be ok, the ht leads are on the distributer in the correct firing order 1,2,4,5,3. The injectors are all working as I've turned it over with them out the manifold and they are atomising as they should be and all the plugs are sparking as I have taken them out and can see a nice spark on all of them.. There's one wire I've attached a picture off which I don't know where it goes near the oil pressure sender? It's 3 pin with 2 red wires and one brown/green... Any help would be appreciated as I'm about ready to bounce it!

[UrS4boy]

After-run pump and fan control module and relay info

There's one wire I've attached a picture off which I don't know where it goes near the oil pressure sender? It's 3 pin with 2 red wires and one brown/green... Any help would be appreciated as I'm about ready to bounce it!

I think that is the S2 V51 after-run pump connector. Two reds and a brown-green:

After-run pump info: http://forums.quattroworld.com/s4s6/msgs/21503.phtml

[Tomhorner]

Thanks!! Was scratching my head for ages on this.. Don't think mine has a after run pump? This wouldn't stop it running on all cylinders though would it?

[Monkeymagic]

So you've got a healthy spark and fuel on all cylinders? Have you checked compression?

[Tomhorner]

It appears to be, I havnt compression checked the engine but it feels like it's got plenty when I turn it over by hand and it ran, started perfect before I taken it apart!

[Monkeymagic]

Just a thought have you got spark on compression stroke. ?

[Tomhorner]

I believe so, I've timed it so that when piston one is at tdc and both the cams are in the air for pot one.. another turn on the crank and the cams have the valves open, so they won't be on compression..

[UrS4boy]

Thanks!! Was scratching my head for ages on this.. Don't think mine has a after run pump? This wouldn't stop it running on all cylinders though would it?

Your 3B should have an after-run pump (AFAIK), at least from the factory.

And yes, regardless, after-run pump or not, nothing to do with running, fuel, spark, etc.

[UrS4boy]

Consolidated 20VT Cam Timing Info

I believe so, I've timed it so that when piston one is at tdc and both the cams are in the air for pot one.. another turn on the crank and the cams have the valves open, so they won't be on compression..

Umm...I have a really bad feeling about your methodology. Proper cam timing is discussed in this post:

http://forums.quattroworld.com/s4s6/msgs/136943.phtml

[twoqu]

The words appear and believe should be replaced with check!
I would go back and check the basic timing alignment using the marks Audi put on the engine and dizzy. As the camshafts turn at half engine speed it is possible to misalign the two using the TDC marks. It needs to be TDC on the compression stroke which can be verified by removing the spark plug on No1 cylinder and listen or feel for the air being forced out. Once that is verified check the dizzy alignment. If they all align and you haven't touched the dizzy cap or the leads, it should be back to working.

[UrS4boy]

It needs to be TDC on the compression stroke which can be verified by removing the spark plug on No1 cylinder and listen or feel for the air being forced out.

Can't you also check this by removing the No.1 plug and gently dropping a Chinese chopstick down the plug hole and then watching the height of the upper end of the chopstick as the engine is rotated?

[Monkeymagic]

I reckon it's timing related personally too.

[Tomhorner]

I have checked the timing numerous times today, the crank timing at the flywheel end and pully end marry up, and the cam timing is as it should be, the tooth with the timing mark on the pully is in line with the v mark on the casing as it should be, the distributer markings marry up aswell and im getting a spark on every pot. ive been told it would run on two cylinders if the cam timing was out? I match marked it all before remove the old cam belt so I know it hadn't moved and the cam in the head havnt been touched ie taken out.. im thinking its electronic? Isit possible to over fuel or for the timing on the injectors to change?

[220bhp]

dizzy alignment on 3b is crucial. not so easy to do in the car unless the you take the inlet manifold of . there are a couple of threads on hear on how to do it .If it is not spot on you will not get full boost among other things. What plugs do you have, and are the leads, rotor arm and cap new.

[Monkeymagic]

Check maf plug too. I don't pretend to know loads On these engines but have seen an aby barely idle due to poor connections