Odd readings of what Ohms Volts?

Can you please explain this in detail including are you measuring Voltage or Ohms and which way around your meter leads are when you take these readings.

What do you mean by 2 live connectors.

The ECU has a transistor that switches one side of the injector to ground.

If you meter the wire going back to the ECU the meter should read open circuit or high resistance and if you swap the + and - meter leads the meter will read low resistance or nearly short circuit.

There are other variables that will effect the meter reading

There should be NO earths on the injector loom with the ECU plugged in with the correct meter lead polarity.

This means the loom is most likely good.

 

Thanks Grant, any thoughts about my coil? I have even gone out and bought a DAC6093 and that has even lower secondary reading of 6800ohms! So have not tried it yet.

 

Thanks for this, i didn't really understand my test results, so will look at the comp/coil and timing, and come back to you. Cheers,

 

I said in an earlier post coil ohms is a useless measurement, if the coil is wrapped with thicker wire the ohms will be less but the coil will still do its job.

 

Finally managed to get the comp test done and it's not good news. The B Bank is all fine ranging from 148-154 psi, and i'm surprised by this because this side of the engine seemed to be producing most of the soot. However 4 and 5A have ZERO compression. Only carried out a dry test, but can't see the point in doing a wet one as they are at ZERO? Wish i comp tested her years ago! What next? Any advise please.

 

Based on what I saw when I pull down my spare engine, sourced from the USA. ALL of my valves were leaking and a couple were really bad, fluid poured out the port when I checked them. You could also have seized rings.

If I you want to fix it properly the only way is the pull the engine, recondition the heads and replace the rings.

You do not have to pull the engine to do this but it does make it easier, and while you at it replace all the gaskets and check/replace idler bearings, and clean up the engine bay.

 

I'm going to borrow a scope to look into the cylinders to see if i can see anything, like a stuck valve. I have also been told that pouring boiling engine oil into the cylinder can free stuck rings? Worth a go before i start major engine work? I will report back!

 

to check for a stuck valve with out doing a compression test... or a scope!

all you need is a feeler gauge and check the valve clearances...

a stuck valve will be out of spec!
and since you know A4 and A5 are 0psi I would start there...

 

Ok, Scope has revealed I have stuck open exhaust valve's on both my zero comp cylinders, they look like they have been stuck for a while, lots of carbon. Is it a case of putting her all back together, disconnecting the injectors on those cylinders and running her to get some heat in her? To recap I have my manifolds and fuel rail still in place. Moral of this sad story is to always start in a logical order!

 

I would remove the inlet manifold, remove the cam cover, and tackle the valves from the stem end. I bit of a lube and a careful tap should do it.
Greg

 

Would I need to remove the cam and the tappets to do this? From memory all you can see is the cam and the top of the tappets with the cam cover off?

 

As the valves are stuck open, I think, repeat think, you could give them a bit of a lever to free them, or tap via a lever, without removing the cams. There must be a gap between the base of the cam lobe and the valve bucket follower if they are stuck open,

 

I'm going to try the lazy way first, and use an additive to see if a good run will help, although I still have the issue of her appearing to run rich on the good side of the engine, so hopefully that lose vernier adjuster may be responsible. Thanks for all the advise so far.

 

OK, as i turn the distributor having loosened off the vernier, the revs pick up, the more i turn it clockwise, the quicker she revs? She is revving at 2500 rpm now at tick-over?? Have i adjusted the distributor too far, or is the overrun caused by something else? I can get the tick-over back by rotating the upper body anticlockwise, but surely if she is wanting to run faster by turning clockwise, does that not show she is timing better?? Or is there another cause for the fast tick-over? It's nice at last to hear run on her own, albeit on 10 cylinders!

 

You need to ensure the timing is correct/at least in the ballpark. Start by ensuring cylinder A1 is at TDC on the firing stroke, then set the rotor so it is just passing the A1 post on the dizzy. After that, moving the dizzy a few degrees only to find a nice sweet spot.
greg

 

I did that earlier and the rotor was just slightly retarded with A1 on TDC? Can advancing the timing too much cause this high tick-over though? I'm going to check the vacuum as i have a feeling poor vacuum could cause my racing tick-over issue. If my vac is compromised then i'm sucking in too much air and the ECU is then over fueling, as a result of no Vac at the ECU, resulting in higher tick over??