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Rb26 Still Wont Start. It Just Dont Make No Sense...

Adrian P

By Adrian P,
in Engines & Forced Induction

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Adrian P Community Regular

Adrian P

Posted
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RB26 conversion into S14 chassis

Fresh rb26 build with pistons / rings, 1.2mm metal headgasket.

I have spark (earthed out the plugs on the rocker cover and have spark on all 6, even took off the boot of coilpack 1 and spaced 10mm from earth and it jumped the gap)

I have fuel (checked all injectors click individually when I turn the CAS,, and after prolong cranking the plugs get slightly wet)

I have fuel pressure (found out old std FPR wasnt holding any pressure, so changed to adjustable FPR and set to 43psi on cranking- as per FSM)

I have timing (used timing gun when cranking, and adjusted CAS to show 20btdc on Ross tuffbond harmonic balancer for r32 gtr, Cam pulleys line up with dots on rear cover at TDC)

I have compression (1: 135psi, 2: 125psi, 3: 140 psi, 4: 145psi, 5: 145psi, 6: 145psi) - keeping in mind that hasnt been run in yet, although no.2 does concern me a bit.

The fuel lines are around the right way (took the line from the rail - not the fpr - and put into 2lt bottle, turned on ign and it pumped into the bottle)

Has 20lt of fresh optimax

Changed spark plugs twice so far with new ones.

Tried start ya bastard and got one or two backfires then nothing

Unplugged the fuel pump and it popped a bit then nothing.

It all cranks fine. I have tried to jump it off my daily when cranking too just in case not enough power.

No error codes on Ecu

Tried to crank without AFMs connected and with WOT, still doesnt do anything.

No o2 sensors connected

Tried without coolant and air temp sensors connected

I have gone over the wiring and all seems good, most of it is the r32 gtr loom uncut and the F4 / m63 connectors spliced together.

I have tried both R32 and a R33 GTR ecu

I would take it to someone as im over it and out of ideas, but its not movable yet. I just want it to start before i put the rest of the car all back together.

WTF!?!

I would think its something simple that ive missed, although now im starting to think its something a bit more sinister (i hope not).

Ill even reward you if you give me something to go on that helps me get more than a cough out of it.

blind_elk Grand Master

blind_elk

Posted
Posted

I've heard RBs like LOTS of timing to start. My RB25 (Wolf ECU) is set to about 45btdc on start.

Is the locating tab in the end of the exhaust cam intact? Otherwise your timing signal might be out, because the CAS isn't correctly located and aligned.

Adrian P Community Regular

Adrian P

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I've heard RBs like LOTS of timing to start. My RB25 (Wolf ECU) is set to about 45btdc on start.

Is the locating tab in the end of the exhaust cam intact? Otherwise your timing signal might be out, because the CAS isn't correctly located and aligned.

Key in the ex cam is still there (have checked this like 5 times becuase the symptoms sound like timing and CAS on wrong, but timing light shows correct fire of no.1 so I wold have thought its on right)

Dont know about the additional timing as im just going by the FSM. ECUtalk shows the ecu reporting 16deg BTDC whilst cranking which should still start... erghh.

GTR260 Proficient

GTR260

Posted
Posted

Where have u taken ur ignition for the ecu from? Does it still get a full 12v when cranking? I had a simmilar issue after doing a ca18det into a pulsar years ago, and the problem was the wire id used for the ecu ignition was dropping voltage when cranking! Found another wire that had full 12v when cranking and it fired first hit! Just my 2cents worth of input

Adrian P Community Regular

Adrian P

Posted
  • Author
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Where have u taken ur ignition for the ecu from? Does it still get a full 12v when cranking? I had a simmilar issue after doing a ca18det into a pulsar years ago, and the problem was the wire id used for the ecu ignition was dropping voltage when cranking! Found another wire that had full 12v when cranking and it fired first hit! Just my 2cents worth of input

Tried that this morning, the wire ive taken for ecu, ignitor / coils, and injectors has 12v when switching from ign to start

Are the injectors stock, and not highflowed?

stock (at least i hope they are) and had them cleaned a few months ago before putting them in.

If u get a backfire the timing must be out

this is what im thinking, but the timing light and all the marks lining up state otherwise... i hope...

Id just try winding the CAS all the way around either way and see what happens.

will try that tomorrow... willing to try anything at this point!

Done anything with the cams/cam timing since?

Just throwing ideas out there...

nah, all seems like it should be right... took the rockers off and checked visually where the cams are pointing at no.1 tdc, (they both point away from each other as the FSM states they should). But i will be trying to move the CAS around as Mat suggests.

  • 4 months later...

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