Jump to content
SAU Community

Recommended Posts

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!!

Link to comment
https://www.sau.com.au/forums/topic/385922-rb26-not-firing-after-rebuild/
Share on other sites

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?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Have a look at that (shitty) pic I posted. You can see AN -4 braided line coming to a -4 to 1/8 BSPT adapter, into a 1/8 BSPT T piece. The Haltech pressure sender is screwed into the long arm of the sender and factory sender (pre your pic) into the T side. You can also see the cable tie holding the whole contraption in place. Is it better than mounting the sender direct to your engine fitting......yes because it removes that vibration as the engine revs out 50 times every lap and that factory sender is pretty big. Is it necessary for you......well I've got no idea, I just don't like something important failing twice so over-engineer it to the moon!
    • Yup. You can get creative and make a sort of "bracket" with cable ties. Put 2 around the sender with a third passing underneath them strapped down against the sender. Then that third one is able to be passed through some hole at right angles to the orientation of the sender. Or some variation on the theme. Yes.... ummm, with caveats? I mean, the sender is BSP and you would likely have AN stuff on the hose, so yes, there would be the adapter you mention. But the block end will either be 1/8 NPT if that thread is still OK in there, or you can drill and tap it out to 1/4 BSP or NPT and use appropriate adapter there. As it stands, your mention of 1/8 BSPT male seems... wrong for the 1/8 NPT female it has to go into. The hose will be better, because even with the bush, the mass of the sender will be "hanging" off a hard threaded connection and will add some stress/strain to that. It might fail in the future. The hose eliminates almost all such risk - but adds in several more threaded connections to leak from! It really should be tapered, but it looks very long in that photo with no taper visible. If you have it in hand you should be able to see if it tapered or not. There technically is no possibility of a mechanical seal with a parallel male in a parallel female, so it is hard to believe that it is parallel male, but weirder things have happened. Maybe it's meant to seat on some surface when screwed in on the original installation? Anyway, at that thread size, parallel in parallel, with tape and goop, will seal just fine.
    • How do you propose I cable tie this: To something securely? Is it really just a case of finding a couple of holes and ziptying it there so it never goes flying or starts dangling around, more or less? Then run a 1/8 BSP Female to [hose adapter of choice?/AN?] and then the opposing fitting at the bush-into-oil-block end? being the hose-into-realistically likely a 1/8 BSPT male) Is this going to provide any real benefit over using a stainless/steel 1/4 to 1/8 BSPT reducing bush? I am making the assumption the OEM sender is BSPT not BSPP/BSP
    • I fashioned a ramp out of a couple of pieces of 140x35 lumber, to get the bumper up slightly, and then one of these is what I use
    • I wouldn't worry about dissimilar metal corrosion, should you just buy/make a steel replacement. There will be thread tape and sealant compound between the metals. The few little spots where they touch each other will be deep inside the joint, unable to get wet. And the alloy block is much much larger than a small steel fitting, so there is plenty of "sacrificial" capacity there. Any bush you put in there will be dissimilar anyway. Either steel or brass. Maybe stainless. All of them are different to the other parts in the chain. But what I said above still applies.
×
×
  • Create New...