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Hi folks.
OK. She cranks well, has heaps of fuel in the rail, yellow spark at the plugs, but just won't kick over.
I'm suspecting timing chain, but some of you know way more than me.
Any ideas please?
Thanks
Orange spark, NOPE, wont cut it. You need a Blue Crack of a spark AT the plug. So coil, cap, rotor,. leads, plugs are the 1st on my list.
Timing chain, I seriously doubt it. They do not give issues, and if they break, never seen that one, or jump a tooth, never seen that one either, the valves do obscene things to each other, and the pistons also get involved. The room for error in there is SMALL. Human involvement and the incorrect initial setting up is the main culprit, and that error is always heard at the first heartbeat of the starter motor.
A mistimed distributor will cause starting/running issues, but if it ran, and now does not, and the distributor has not been moved, scratch that.
#1 cylinder is at the rear on the engine, in case you did not know.
Injector pulse not taking place would mean dry spark plugs after trying to start it, so try to start, pull a plug, wet or dry??
Doug will slide by when the time zones drop into place with other ideas, as he is the S3 Guru.
Heaps of fuel at the rail is good....but what's the fuel pressure and are the injectors working? We can wait, perhaps, on checking fuel pressure but working injectors are a must. Have a helper crank the engine while you listen. If you don't have a mechanic's stethoscope use a long screwdriver....one end on the injector and the other at your ear. You should hear a clicking
And, what's the history here? has the car been in storage? Is the fuel stale? Did this problem just occur out of the blue?
Speaking of blue, that's what color spark needs to be: blue/white. Yellow is weak. How are the plugs wires, distributor cap, distributor cap, and coil? If your coil has a ballast resistor (some do, some don't), run a jumper from the battery "+" post to the "+" post of the coil and see if anything changes.
There. That oughta be enough to get the discussion going
Was running fine on Friday, flat battery Saturday morning, no jumper leads, so swapped my battery for a mate's just to start vehicle, put mine back in and drove home.
Yesterday, cranked well but no running and flattened battery trying to get it to kick over, used other vehicle to jump, again, cranks well, but that's it.
During this, I checked the wires etc and oulled
Continued.....
Pulled 1 and 3 plugs separately, both have yellow spark.
Replaced coil recently and vehicle does have a ballarst.
Plugs damp when removed.
You have juice inside the cylinders, so EFI is deemed working.
The spark is an issue. Ballast systems ALWAYS have a by-pass wire that goes direct to the coil +ve during cracking to give the coil a 12v whack to supply the required spark to start the engine. This wire is "usually" from a dedicatef terminal on the starter relay.
Mostly that ballast is removed, as they reek havoc, and that cures the spark issue. Doug will fine tune these details when he gets here.
I used a Fuel Miser CC215 Coil on one recently, but there was NO ballast fitted.
From the coil, there are 2 wires running directly to the electronic ignition amplifier. It has 2 wires on a plug on it's side going to the distributor. One wire from each pole of the coil. One pole has 2 plugs, one to the amp and the other disappears down below the distributor. The other has 3. 1 to the amp, 1 that goes backwards into the top harness and the other disappears down below. On the inside of the guard just below and forward of the air filter box that says it's a 2pr power resistor.
Thanks heaps so far, hope this bit helps.
Cheers
From the coil, there are 2 wires running directly to the electronic ignition amplifier. It has 2 wires on a plug on it's side going to the distributor. One wire from each pole of the coil. One pole has 2 plugs, one to the amp and the other disappears down below the distributor. The other has 3. 1 to the amp, 1 that goes backwards into the top harness and the other disappears down below. On the inside of the guard just below and forward of the air filter box that says it's a 2pr power resistor.
Thanks heaps so far, hope this bit helps.
Cheers
Wire colors would even more helpful
I agree that weak spark is an issue.
Before we go further.......
What year is this car? Almost all Series III 4.2 cars had Lucas CEI--Constant Energy Ignition. A few early cars, for certain markets, still had the older Lucas Opus ignition. Very different systems. I couldn't tell you a thing about OPUS, but Grant can.
The Lucas CEI is easily recognizable by the having the ignition amplifier mounted to the front of the inlet manifold. The amplifier itself is roughly square, about 4" x 4" (see picture)
*IF* you have Lucas CEI the ballast should be mounted directly to the coil "+" post. (see picture) It'll have two white wires attached. Remove the ballast and attach to two white wires to the coil "+" post. The "-" post will typically have black/white wires and a white/slate (or white/slate/blue) wire....with the tracer stripes being spiral, not straight.
What coil did you use? For the CEI you need a 12v coil with about 1.0 ohm primary resistance.
It's a rare, rare day that I can disagree with Grant but the Lucas CEI on the 4.2s did not use the 'bypass' circuit for the ballast. The ballast, when used, was 'inline' at all times. This is probably the only car you'll ever see with this configuration!
The "2pr Power Resistor" is for the fuel injectors, not the ignition.
Might have found part of the reason. At least all efi wiring in good condition. Will just retape the harness but replacing the white with black stripe going from the coil back to the plug at the start of the injector harness, the green that goes to the sensor above injectors 3&4 from somewhere down below and the wires (white and white/black stripe down to the amplifier.
From coil to efi harness Green wire from sensor behind coil on water rail to down below somewhere.
timing chain
