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Hi there, after completing my rb26 engine r&i the car wont idle or run without dumping copious amounts of fuel out of the exhaust.

what is odd to me is that the car was idling fine. The battery wont charge however the terminal and alt shows 14v while running. (Tried new batt) but to no avail.

The car was idling fine until the battery started to die and the idle got lower and lower until all of a sudden the tick off a relay was heard and instant shutdown. The car started back up but from then on ran super rough, wont idle at all and is rich and sluggish to free rev. Forget driving it, seems to build boost but not accelerate and just dumps fuel in.

checked vac lines, fuses that I thought pertained to my issue and bought a new battery. None of which made a difference.

the wierdest thing of all is that the intakes pulse one after the other at idle as if the bovs are recirculating air. I tried blocking the reference off but made no difference.

Is it likely that the voltage drop caused a spike just as the car shut down and damaged a component? Apparently im hopeless at electrics but im open to instructions

Rb26

GT2540s

stock gtr bovs

haltech plat pro ecu.

twin walbro e85 pumps on with relay.

also worth mentioning alt gets fairly warm after running for only a few mins. Block is earthed, alt privides 14v wtf

(Confused and frustrated)

Blake

Have you checked your spark plugs, starter motor power cable connected properly, if all ok check your timing to make sure the haltec is reading the same as your timing light. Sounds as though the timing is retarded for some reason.

No I didnt check the plugs as it was running fine one minute then all of sudden no dice. I have adjusted the CAS by hand but that didnt help. Perhaps putting a timing light will tell me whether or not the CAS has died and is excessively retarding my timing no matter how far I advance it (its currently in the neutral position) yes I have tried the starter lead also. I am getting 14.3v to the battery. I cant explain the shuffling between intakes though.

Edited by 6InlineTT

Okay, I have some interesting info. I noticed when I bought the car the a/c compressor was unplugged on return from having the Haltech fitted. Apparently the haltech is not compatible with the skylines "direct 12v feed a/c compressor). So unknowingly I have plugged it back in.

When I connect my battery up, I can hear the compressor clutch engage which tells me it's drawing power when the car is off. Perhaps my haltech has reverted to factory plug n play settings for the stock rb26 injector slope. Mine are 1000cc. This would explain the super rich nature of the tune and possibly be part of the super fast battery drains.?

tomorrow night I will know for sure

forums.haltech.com/viewtopic.php?f=28&t=10543

Apparently, You need to wire in a relay or something I'm not sure. Perhaps only on certain cars or models or eng swaps. My car is a GTfour using rb26 with combo of gtr and rb25 accessories. This is a steep learning curve for me so take what I say with a grain of salt haha.

Edited by 6InlineTT

Unugged the A/C compressor. Battery problem solved.

Base timing on the haltech shows 24-28deg at idle but i had to add 20degrees advance so it will run normally. Total advance reads around 50deg while base timing sits at 20.

I think my CAS is dodgy?

50deg advance seems excessive but the cars runs like its only at 20deg or so. I guess i need a timing light.

You need to check it with a light off the crank before you do anything. If there is that much variance with a light then it may be the dreaded modern ecu/ cas issue where the only real remedy is a crank trigger. But don't do anything until you test it with a light.

Ahh okay. Ill grab light tomorrow.

Considering it was running fine before the battery died while it was running I will hope that Its the CAS.. or I am a spastic

I set the timing via the cas to about 20degrees using the timing light. The car was very sluggish to free rev until I added timing correction +15deg now its perfect. I will take it for a spin tonight and check timing under boost. I swapped to e85 today aswell for added safety and adjusted then fuel trim up 30% seems to run fine. I am a little worried about excessive igntion timing but at the same time its the only way the car will run.

also I was thinking my vernier cam gear that is advanced 2degrees would alter my CAS output? Thus reading more advanced with the timing light than it truly is?

  • 5 weeks later...

Did some cas trigger angle pickup trickery with the haltech to get the cas to read the same as the ecu, 17.5psi @14degrees timing 305rwkw with good AFRs.

Recirc issue gone, car drives great. Time to add some timing and boost. How much, I'm not sure?

http://www.sau.com.au/forums/topic/452568-rb26-e-flex-ignition-vs-boost/

Thank you for the assistance :)

I do but it's going in with the new exhaust. I ran it up on the dyno to check AFRs. .80lmda or 11.7:1 pretty steady on boost. The car made 312awkw on hks GTSS twins @21psi before the 2540s went on. So I figure I'll adjust slowly to 21psi and play with timing then while watching the knock levels. When I'm happy with it I'll dial it back a degree and leave it there. I was just curious to see what others are ballpark running.

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