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A week ago i was driving on the highway car was running beautiful and then it made a small backfire noise started missing and then died when my foot hit the clutch.

I towed it home and now it won't start.

I have put another cas sensor on it and same story.

I have since checked.

Timing and it was all good.

Spark and coils working fine.

Pulled plug off injectors and checked with multimeter which showed no volts and then 10 when it pulsed. Not sure if that is ok.

Fuel rail is pressurizing and the pump is priming.

Battery shows 12.4 volts but engine is turning over slowly.

Could it not be starting due to not cranking fast enough.

Please help it's killing me not knowing.

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No it should still fire regardless of whether the cooler pipes are on, might just need some throttle as the un-metered air makes is screwy. Unplug both AFM's and try again, this will put it into a limp home mode which makes the AFR's a bit better for starting.

First point of call if you running a standard ECU is to put it into diags and look for fault codes. Takes so much guess work away from something like this. If you haven't already done this then please try that next.

After that I would do this:

1. Pull fuel line going to rail and check fuel comes out with the first 10 sec prime with ACC on.

2. Pull coil and spark out of no1

3. Pull fuel pump relay out after testing rail pressure

4. Switch IGN to ON

5. Remove CAS and spin it over by hand the direction of the motor (Clockwise with the CAS facing it's orginal position)

6. Verify coil no1 you pulled out earlier sparks (Insure spark is grounding on cylinder head properly)

7. Verify you can hear the injectors ticking, should be quite noticeable without the noise of the motor cranking

See how you go.

Have you got compression?

Injectors should have constant 12V on one pin, the other pin gets switched to earth by the ECU.

There should be a tutorial on how to get diagnostics.

(And how do you check timing if the engine won't run?)

it could be from the piping as said, my r33 had the same proplem it back fired a little then shut off, it still started everytime it clonked out. the intercoller pipe was out leading from the manifold

If ur handy with auto electrics at all. Try running a wire from the positive on the battery to the injector positive(make sure its the positive, should be the same colour wire on all injectors) U only have to connect to 1 of the injector positive wires as there all connected to 1 source. See if ur car starts now. If it does then there might be a break in ur wiring loom somewhere or the ecu injector drive might be fried.

All motors just need three things - air, fuel & spark.

On my Autronic, if the computer doesn't get at least 12.5v then it will not start even if it will crank over. Be sure to charge up the battery to be sure the ECU is getting full voltage.

By the way you said it stopped sounds like fuel or spark to me.

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