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Hi all,

As above has spark no injectors. This is a conversion in a Mazda Bravo so has the ECU BCM disabled with a chip.

I have tried another ECU (moved the chip over) same issue. Injectors click with 12V applied. I have another DFI module but not sure if this is any good either. New CAS installed. Had a gas conversion removed so maybe the way that disconnects the pump fuel is causing an issue?

This issue has been intermittent for more than 6 months, where when cold would start and run all good. Then park up and try to start hot and no go. Wait a while and then off we go.
Think thats all.

Not sure where to go from here?

My first guess is CAS but you have replaced it. With a new one? I hope so. Does the fuel pump prime up when cranking when the engine cuts out? If my guess is correct try pouring cold water on it when the engine cuts out and if it goes you found the problem.

New CAS.

Fuel pump primes when key is turned to start. I have shorted out the fuel pump relay so pump stays on and it still will not start.

The engine no longer starts hot or cold so not sure if water is going help.

Try the DFI if you have a spare as the DFI controls the timing when cranking until the engine hits 400rpm (IIRC) and then the PCM takes over control of the ignition timing.

Are the injectors getting power and do they stay powered while cranking

The injectors have power, however I have not checked if they stay powered. Will check now.

[quote="immortality"]Try the DFI if you have a spare as the DFI controls the timing when cranking until the engine hits 400rpm (IIRC) and then the PCM takes over control of the ignition

Ok so I put back the original DFI that I replaced a few months ago when trying to sort this intermittent issue. Same result. Question is do I have 2 faulty dfi units? I definitely have spark does the dfi stop injectors firing?

delcowizzid wrote:Are the injectors getting power and do they stay powered while cranking

Injectors have power even when cranking.

series8rx7 wrote:

immortality wrote:Try the DFI if you have a spare as the DFI controls the timing when cranking until the engine hits 400rpm (IIRC) and then the PCM takes over control of the ignition

Ok so I put back the original DFI that I replaced a few months ago when trying to sort this intermittent issue. Same result. Question is do I have 2 faulty dfi units? I definitely have spark does the dfi stop injectors firing?

Or a wiring issue. The DFI controls the ignition timing during cranking but If I understand it correctly, it still sends a signal to the PCM that it uses for the fuel injection timing. The PCM needs the signal from all 3 timing sensors 18x and 3x from the CAS and the cam sensor to determine the proper sequential timing sequence position. Without the cam sensor signal the system is supposed to default back to batch fire mode.

Do you have the ability to datalog?

No I don’t have any data log ability.

Wiring issue is a possibility but I am not sure where to start?

Haven’t tried a CAM sensor but I have read it should start without this.