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need sum help guys i done a rb25 conversion got the engine to run pulled it out and painted my car. i refitted the 25 and it just cranks over and ive got no spark or injector pulse. ive tried different cas, ecus and replaced the ignitor module. ive check continuity on all the ecu pin outs. ive check every sensor for power and earth and still not a thing any ideas? its starting to really shit me

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if you are getting power to the injectors and coils i'd be making sure a pin hasn't backed out of a plug somwhere. other then that you've replaced everything that could cause it. double check all the power supplies at your computer again and check if you are getting a pulse on the injector outputs.

Unplug EVERYTHING (and I mean EVERYTHING)

THEN, Plug it all back in.

Seriously, don't just do one or two plugs, do EVERY SINGLE plug.

You'll find you've left one plug out, or a relay out, or a fuse.

When you redo it, it'll all be sweet.

  • 4 weeks later...

I had the exact same symptomes as you except my car left me stranded 2 hours from home. Parked it and it wouldn't start. It would crank and crank, but not even a sputter. My MAF was working properly and I was getting fuel because I could smell it. After checking every plug, nothing got it to work. I replaced the ignitor module with a known good one, still didn't fire at all. Went to check for spark and as we were checking, for spark with 3 of the coils pulled and the other 3 on the engine, the engine tried to start with 3 cylinders firing and the one plug out was sparking too. Turned out that somehow the power was getting grounded before the coils or wasn't getting grounded at all. After inspection, I still couldn't find anything wrong with the coilpack harness, but it started up and drove all the way home without issue. Totally pissed me off mostly because there was "nothing wrong". Readjust the coilpack harness and confirm the ground loop on the rear coilpack assembly bolt. At least it's free! :(

Edited by Darius

have you checked the two basic things?

fuel and spark?

Are the injectors opening, get the special injector bulb that clips into the injector plug and crank it over, make sure the light pulses (proving that you are getting both constant power and signal to the injectors)

Check the fuel pump is actually priming the rail, undo the fuel line and turn the car onto the on position and physically watch fuel come out.

Take out a coil, with the spark plug still in it, earth the plug out and crank the car over to make sure there definately is a strong spark.

If its got fuel and spark there should be atleast a kick out of it

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