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I am working on my mate's R34 RB25de NEO car and he has a really strange issue.

I have confirmed via Nissan FAST that his car is indeed a non Turbo automatic and I have also confirmed his actual ECU is for a non Turbo r34 automatic.

The issue is this;

when I connect via consult port with Nissan datascan or ecutalk or conzult etc they all say that his timing is 10deg btdc and it jumps around to as low as 3 or 4deg and as high as 12 to 15deg at idle. Tps voltage is perfect. The engines timing was set to 10deg also. His car was randomly dieing while on the move.

The r34 fsm says it is supposed to be 15deg btdc and I've set it to that but why does ecu expect 10deg?

Any ideas?

Do I need another ecu?

If so, anyone have a non Turbo r34 auto ecu to give away?

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Also, what are the consequences of having the ECU expecting 10deg btdc and actually setting the engine at 15deg btdc??

Could the issue actually be a Nissan ECU programming mistake???

The engine is actually a 2.5L NA Neo engine which the R34 FSM says has to be set at 15deg btdc.

you can't actually check the timing via a consult cable unless you actually have a timing light as well. and to set the timing you need to put the car into base idle mode, which locks the timing (generally at 15 degrees). at idle it is normal for the timing to jump around a bit.

but as long as the timing that you see with a timing light and the timing you are seeing on the consult are the same then there is nothing to worry about.

Oops, I should have also mentioned that with a timing light the timing had been set to 10deg and there ecu also said 10deg.

Now I know the ecu is static and can't be altered. So the ecu saying 10deg in base timing mode for a 2.5L Rb feels wrong due to all the Nissan service manuals saying that all 2.0L RBs should be set to 10deg, all 2.5LRBs should be 15deg and all 2.6L RBs should be 20deg at stock.

So this ecu seems wrong. But if someone had an Auto r34 ecu non turbo I could borrow or have our even buy in Melbourne that would help me heaps

Yes I had it base idle mode/timing mode and rpm was at 600 as per manual. Quite literally by the book. That's what is weird, The ECU seems to think normal is 10deg. Its got me stumped

Edited by THRLLR

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