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Hey guys, in short, I've had my engine rebuilt, and after reinstalling, can't get it to fire, not even a cough. There's fuel, deffo got compression, but no spark.

Specifics: it's an r33 rb26, in a vl. Wiring was professionally done, and before the rebuild it was all good. Stock computer, no big injectors or anything.

Rebuild was done by a mate, who's done a few race engines, but his first rb26. I have no doubt he's done right. Basic mild rebuild, pistons, rods etc. turbos have been hi flowed, steel wheeled etc. (mate is 500km away, so not keen to trailer there to look over it)

Took it to a local mechanic (country vic) who put it down to an intermittent fault and wouldn't go any further.

Everything I've done on a budget, and after returning from os, haven't got cash to splash around, missus is preggers, so just taking it to an auto elec with an open cheque book is the last thing I'll do.

Any suggestions on where to start, cas, afm? Is there something incredibly stupid that I'm missing?

Any suggestions gratefully accepted!!

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Local guy is an idiot, how is it intermittant if it wont start. If there is injector pulse, then it wont be cas, does the fuel pump come on with ignition for a few seconds, and then again when cranking? Power at the coils, Ecu and igniter/coils earthed? Are you sure there is no spark? You can measure Afm voltage with ignition on at the ecu to confirm wiring and afm's. How do the plugs look? Maybe Double check the cam timing, and while you are at it does it still have the locating pin in teh front of the exhaust cam to align the cas?

Thanks for the replies lads, gives me somewhere to start, would be amazing if it's just those two plugs in the wrong spot. I'll get in and have a crack after work and see where it leads!

Rolls, the wiring was done by a company who do heaps of conversions, this was the first one of this kind, so fingers crossed it hasn't gone tits up there. As said, was previously running as is, so hopefully not!

Back of the inlet manifold there is 2 plugs that can be swapped by accident. Check and swap these. Has happened to me tooThey connect to the coilpack / ignitor loom

Thanks for the replies lads, gives me somewhere to start, would be amazing if it's just those two plugs in the wrong spot.

hahaha Nissan are normally so good about this....but there are indeed 2 plugs that fit together the wrong way around and will stop spark on the 32 gtr loom. you'll always remember after the first time you do it :P

Update:

There's power at all the coil packs (just over 10 volt each). There's power at the relays at the ecu when ignition is off (12v) but its still there when the ignition is on, so obv relays aren't actuating, and we have a problem.

Unsure if related, but fuel pump is not coming on with ignition either.

Assume there is a failure in power supply somewhere?

Also, unrelated I think, found that the earth cable to the battery was busted, now fixed.

Ecu and coils/ ign are earthed.

Pulled cas off, locating pin is there, connected the plug and spun with my fingers and got nothing from the injectors. Tried with a second cas for same result. Assume this is also a problem from relays not locking in.

If theres power at the coilpacks, use an led test light to see if they are pulsing when cranking,

If no

Use led test light to see if there is a pulse before the ignitor.

This test will tell u if the ecu is outputting a signal to the ignitor and if the ignitor is recieving and outputting a signal to the coils.

If pulse before ignitor but none out need new ignitor.

No pulse before ignitor ecu, cas or wiring issue

Is the tacho moving when u crank?

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