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As i was driving the car around this morning the engine died and i couldnt restart it, since getting it towed home i have done the following checks.

I have checked and it is getting spark, the guts of the ignitor look fine

The injectors are getting fuel to the rail and they are firing (removed the rail/injectors and cranked engine over, fuel pump does the pre crank prime too)

Throttle position sensor is reading correctly, i can only assume the CAS is working correctly as spark and fuel are being triggered in the correct order.

Fuses have all been checked and are all OK.

Timing belt marks all line up but even skipping 2 teeth it would still start.

Pressing the throttle to about 50% while cranking did get it started once, i moved the revs between 2000-3000 but as i was doing that it died after about 5 seconds of running (AFR was showing 11.4:1 at the time).

I have no idea what on earth else it could be. Any ideas?

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Does pressing the throttle to 50% start it now? Or was that a one time thing. If it starts again under 50% throttle but dies when you shut the throttle your AAC valve may be stuck shut.

Does the cranking sound normal to you (ie, lumpy.. like it's still getting good compression). Does it ever almost fire or is it just dead dead?

Sounds like you've checked the basics pretty thoroughly.. Check the AFM connector if the ECU logs a fault there then the engine will run like a pile of poo and starting may be really difficult too.

Does pressing the throttle to 50% start it now? Or was that a one time thing. If it starts again under 50% throttle but dies when you shut the throttle your AAC valve may be stuck shut.

Does the cranking sound normal to you (ie, lumpy.. like it's still getting good compression). Does it ever almost fire or is it just dead dead?

Sounds like you've checked the basics pretty thoroughly.. Check the AFM connector if the ECU logs a fault there then the engine will run like a pile of poo and starting may be really difficult too.

Even if the AAC valve is stuck shut i was driving when it initially cut out/stalled not stationary/idling and when it did start while holding the throttle open it also stalled with the throttle open not closed.

It cranks normally, but doesnt fire/pop/splutter/anything.

The ECU is MAP based so no AFM, MAP sensor is giving a signal to the ecu

Engine?

25/30 but that shouldn't make any difference.

Buy a new car?

har har

all intake/cooler pipes are on and secure, i did check the spark plugs and they look fine (they are only 6 days old, as is the whole engine, setup had been working perfectly up until today).

map sensor readings looked normal, but i can double check tomorrow.

i checked and fuel flow is fine so unlikely to be the filter, pumped out 1L in a few of seconds of priming.

What is the fuel pressure?

Have you checked compression readings?

dont have the tools on hand to check those at the moment.

Are u running a top timing beltcover?

Check the cas hasnt snapped the shaft

Yes i am, always have done. the half moons are still in place.

Would the car start or run if the map sensor line had been cut or popped off?

Checked the line from engine to ECU all still firmly attached, map readings go up and down if pressure/vac is applied to the engine side of the line and i also checked for leaks, line holds pressure fine.

I'm surprised you haven't fouled your spark plugs after that many failed attempts. My car died on my, tried so many different things and then noticed all the failed starts flooded my plugs. I would still see a spark but there was no way they would fire in the engine and my battery died trying. New plugs and it was fine. Just because you can see the spark outside the cylinder does not mean it well hold up when there is fuel in there and compression occurring. If the plug is could the spark won't last or seize to exist.

Use a timing light and see if its sparking at the correct time. I had a cas shaft snap an still sparked etc but wasnt at the correct time.

As with the compression and fuel pressure tests i wont be able to do them until i can get my hands on the tools (hopefully i can borrow them monday night)

I'm surprised you haven't fouled your spark plugs after that many failed attempts. My car died on my, tried so many different things and then noticed all the failed starts flooded my plugs. I would still see a spark but there was no way they would fire in the engine and my battery died trying. New plugs and it was fine. Just because you can see the spark outside the cylinder does not mean it well hold up when there is fuel in there and compression occurring. If the plug is could the spark won't last or seize to exist.

Just tried different plugs with the same coil packs and then with different coil packs, no difference.

What is the fuel pressure?

Have you checked compression readings?

Fuel pressure, when priming steady 45psi, when cranking 40psi

Compression results. (cold and dry test)

1. 160

2. 175

3. 170

4. 160

5. 160

6. 160

Use a timing light and see if its sparking at the correct time. I had a cas shaft snap an still sparked etc but wasnt at the correct time.

tried a timing light on it but it didnt seem compatible with the coilpack setup sparkplug would spark but no flash from the timing light.

will hopefully borrow another cas on the weekend and test with that see if that gets it going.

put a high tension lead between the coil pack and the spark plug and attach ur timing light to that... :)

also sounds like a timing issue :S or low fuel pressure but uve solved that .... im thinking air idle control valve try remove it pull it apart and clean it out with some solvent (evaporative) solution i dont know if they cause a non starting issue maby their cleaned for more of a hunting issue... try it anyway

put a high tension lead between the coil pack and the spark plug and attach ur timing light to that... :)

also sounds like a timing issue :S or low fuel pressure but uve solved that .... im thinking air idle control valve try remove it pull it apart and clean it out with some solvent (evaporative) solution i dont know if they cause a non starting issue maby their cleaned for more of a hunting issue... try it anyway

even with the throttle opened it doesn't start. which it would if it was just the idle control valve not working. as for the high tension lead into the coil, that never occured to me but at this point im happy to just wait untill i can get my hands on a known working cas and ignitor to test.

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