S14 SR20DET Engine and ECU on S13 chassis strange cut

[louiswun]

Its happen in the middle of tuning section,
Main fuel map copied to knock fuel map,
Main timing map copied to knock timing map,
K value around 24300
Latency around 660
I did not have log on this tuning section.
ECU is 69F00
Any reason the ECU will cut like this ?
The rev limit was set to 7,800 rpm
http://www.youtube.com/watch?v=I1egfcS5WyQ

[skylinegtrhr]

Hi Louiswun,engine is stock?
Did You do conversion ? I presume that car was running OK on street?

[Matt]

Put 74F00 (JDM) or 75F00 (EDM) on the board and try it again. 69F00 image has some strange bug with cutting out. We never load up that particular image on boards here I program and mail out

[PL]

I've had problems with the 69F00 image too - but not as you describe. What I've seen happens only after the engine has idled untouched for about 3 mins. At which point it goes into a weird limp mode and won't rev above 2500. Re-start and it's fine again. Seen this on 3 different cars now.

For that reason I always put 74Fxx images into 69Fxx ECU's these days. I recently found that at 74F01 they removed the boost pressure sensor. Many engine conversions don't fit the boost sensor, leading to a boost sensor DTC. This doesn't seem to have any ill affects but just to be sure I'd use 74F01 image instead of 74F00.

PL

[louiswun]

Engine is stock, but with 256 In/Ex cam, a greddy copy intake plenum, S15 TB (I'm not not sure, owner tell it is), used to be puprple 550cc side feed injectors, Z32 AFM.....
Engine swap was not done by me, I only do the pipe work and install Nismo 740cc injectors, fuel pump...etc
This car is mod from a street car and tune for a drift race held at 25Nov2012,
I have no chance to test it on the street (no valid licence fee) after the tuning, external wastegate too noisy to attract traffic police.
The whole November was road block everywhere due to Macau GP, the traffic police was focus on modified cars.
After this cut, I have richen up the mixture a bit and pulled around 2 degree of timing, It pulls fine.
This car does not connected netural switch, could this be a problem ?
May be that cut is some kind of engine protection, I am not sure but I can hear the engine sound fidgety just before the cut.

edit :
This S13 originally CA18DET 5MT with standard speed clucter,
The owner installed a JDM S13 CA18DET digital type speed cluster, but it never works normal (even when it is CA18DET 5MT).
Now, it is 6MT gear box, main chassis harness is still CA18DET, Enigne and engine harness is come from S14 SR20DET,
it link with a special adapter, Japan made for S13 CA18DET chassis for using with S14 SR20DET engine
(If I remember right , the maker company named MEKO...not sure...brought it used from Japan many years ago)
When I'm crusing at around 80 km/h on highway, the digital cluster only show around 40 km/h,
but the ECU speed signal is showing 3XX km/h

[PL]

Hmmm. Sounds like all the hallmarks of a trouble car!!!

Hey, it's not just boost cut is it??? "TP Load Limit".

Usually neutral switch doesn't matter. But check in NIStune to make sure it's not showing Neutral Switch ON. The switch is usually left open for engine conversions = ECU thinks it's in gear all the time. Can affect idle a bit but that's about all. Neutral switch wire shorted to GND indicates car is in neutral to the ECU.

PL

[louiswun]

Hmmm. Sounds like all the hallmarks of a trouble car!!!

Hey, it's not just boost cut is it??? "TP Load Limit".

Usually neutral switch doesn't matter. But check in NIStune to make sure it's not showing Neutral Switch ON. The switch is usually left open for engine conversions = ECU thinks it's in gear all the time. Can affect idle a bit but that's about all. Neutral switch wire shorted to GND indicates car is in neutral to the ECU.

PL

Thanks PL
here is what in the TP lImit
136 136 136 136 136 136 136 136 136 136 136 136 136 141 141 141
but pulling at 1.3 bar still the same setting without cutting.

[PL]

Be worth temporarily adjusting it higher to check.

Shame it's a track car. Makes it hard!!!

PL