My first project is my Citroen CX 25 Gti Turbo 2. It's a 4 cylinder, side cam 8 valve, 2500cc, 1:8.5 compression turbocharged, intercooled, wasted spark engine.
MembersPage/EvertDuindam/CXFactorySetup
Airflow and airtemp signals come from a mechanical airflow meter. There is a GM 16 038 77 MAP sensor, but the signal is only used by the electronic ignition, not by the injection. There is a watertemp sensor, no lambda or EGT. There is a knock sensor type E 001T - 90272. It looks to me like the ignition modules are logic level as the Revue Technique speaks of two circuits one at 1-1,2 Ohm and one at 3500-4000 Ohm.
The RPM pickup is done from the flywheel which is a 72-1 setup with a BDP sensor (which I am now thinking must be a HALL (partnumber EA 20 165 653 with a claimed resistance of 50 Ohm according to the Revue Technique).
- if it's HALL, you can measure output with DVM (ignition on). Push the car a bit in gear 5 and the output will switch between 0 and 5V as the teeth pass
I would like to set up a VEMS for the vehicle in order to increase fuelling and accomodate anything I would like to do in the future. For now, my objective is about 250hp, which should be equivalent of about 1.2 bar boost.
Now, the first thing I need to set up is a buy list. I'm thinking a pre-built VEMS, (do NOT need a 1 wire interface), a 4+4 ignition driver (just incase I'm wrong about the logic level), 400kpa onboard MAP sensor, LCD & PS2 for ease of use, knock and EGT sensing, screws
- 30V flyback since you have a resistor pack (and you'll finally use high impedance injectors like the 630cc/min at 3 bar) anyway
- primary trigger=VR
- secondary trigger=HALL
Obviously I'd also want a WBO2 sensor, and some wiring, like the 36pin and 18 pin harnesses and plugs.
As I have an air meter, I'm going to want to replace that, and will probably need a replacement air temp sensor. Are there any suggestions for that?
See genboard/sensors under WebShop (MAT sensor; and Temperature sensor (NTC) - latter only for the experienced.
The car doesn't have a stepper motor, in the factory setup cold enrichment is done through the standard injectors.
- stepper motor (or in general idle air valve) adds AIR
- injectors add fuel
Trigger - current state
Please keep an updated version of the current state here. Organize thematically, not historically (or not only historically).
I have made the following page to keep the information about the primary triggger.
MembersPage/EvertDuindam/PrimaryTrigger
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MembersPage/EvertDuindam/ProjectPics
MembersPage/EvertDuindam/IgnitionMatters
MembersPage/EvertDuindam/RpmOutput
MembersPage/EvertDuindam/CitroenSM
MembersPage/EvertDuindam/CXGtiTupdateHistory