Hello.

I need help for finishing my ITB setup on a B16A2.
The specs are:
- OBX ITB modified (new/better synch screws, new vaccum outlets on all the bodies)
- P28 chipped ecu
- stock cams now
- stock 240cc injectors high Z

I have done a lot of work on this setup.

Bodies are perfectly synch with a carbtune.
Injectors are ultrasonic cleaned with new seals.
O2 and TPS sensores are NEWs.
ECU is a classic P28.
Software used is Crome 1.5.3 (bored with the last one, expiration problems) with base B16 maps (ITB Tool, RTP, cheksum, openloop, no IAC).
No Crome gold map (even if i own a real licence !)
TPS is perfectly mounted (Clean 0 to 100% band during logging).
Good job on vaccum lines with a great vaccum tank.

Curently working with a cross map MAP/TPS (ITB tool).
MAP info is stable (...Very hard to have a stable MAP value ... Need a really clean vaccum work).
TPS work perfectly.
Starting to make the first cam fuel map (vtec disable).

My headache is:

Why my ECU stop outputing injector pulse at 1600RPM between 0 and 10% throttle angle (!!!)
See with my scope, the problem is the software/parameter/ecu, not the ITB setup :-/
the 1600RPM deadline :-( ... the engine cut at this regime (fuel cut off).
tryed ALL possibilities (rich, lean, lot of advance, nul advance) ... nothing :-(
is it a fuel cut off problem (foot lift cut off ?)

above 10% of throttle angle, all is OK.

Please, don't tell me to use Neptune (price of a S300 daughterboard...)
AlphaN will be probably the best but MAP/TPS mix is great with a good/stable MAP signal (my case).


Here is the video of the engine bogging at 1600RPM (and injector 1 's output falling at the scope) - crank the volume :-) :
http://theangel540.free.fr/EK4/WP_20220317_002.mp4
http://theangel540.free.fr/EK4/WP_20211030_008.mp4

 

I don't have my Crome software with me at the moment and I don't remember exactly how the ITB tools work for transition from MAP to TPS. Could be the crossover (MAP Hg vs TPS %) needs to be adjusted a little bit.

 

Thank for your help!
have found the solution!
I presume it'll help a lot for peoples with same trouble.
You must mount the TPS sensor at 10% in stand-off position.
I presume, the stock micro code see TPS values below 10% at "foot up"/stand-off position.
That means ECU work, in this area, with fuel cutoff (fuel economies) and backup below 1500rpm (!).
It explain my fuel cutoff at above 1500rpm (!!!).

Here is the engine working with a 10% TPS lowest value:

http://theangel540.free.fr/WP_20220319_001.mp4

...3 months for finding this :-/

 

Glad to hear that you got it fixed.

I always make sure when I install a TPS for the first time that my voltmeter reads between 0.48v - 0.52v at closed throttle. Then WOT should end up to be around 4.5v - 5v

Just out of curiosity, what is your TPS voltage when it is showing it at 10%?