[rusEfi] 1996 Ford Aspire #1!

[AndreyB]

That would be the technical thread about my test vehicle


Sequential injection, stock ECU uses MAF as an engine load sensor. There is a single coil inside the distributor.

The two signals from camshaft position sensor are


Injectors: Denso 195500-2110, 120cc, purple, 13.9 ohms

Single ignition coil: low-side driven with 5v pull-up resistor

MAF sensor outputs current, in the stock ECU a 1000 Ohm pull-down resistor is used.

Current mods: Honda MAP sensor

[AndreyB]

The bare minimum of wires to start the car would be

1U fuel pump
2B/9 MAF sensor
3A/1 GND
3B/14 +12 power in start & run
3C GND
3F CKP sensor
3G CID sensor
3N/20 spark out
3U, 3V, 3W, 3X injectors

[AndreyB]

Phase #2:
2F/11 throttle position sensor (TPS)
2I/5 Vref: +5v TPS power supply
2G/4 engine coolant temperature (CLT)
2O/8 'sensor return' - that's another GND needed for the sensors to function
3Q/9 Idle Air Control valve (IAC)
1E/3 Malfunction Indicator Light (MIL)

[AndreyB]

Everything begins with cranking and cranking is pretty interesting. Stock Aspire ECU logic for cranking is
a) ignition dwell is controlled directly by the secondary camshaft trigger wheel: coil starts charging on the tooth start and fires at the tooth end. So, ignition dwell is defined in angle, not in absolute time as in running mode. Another thing worth noting is that cranking speed is not exactly constant, this should be considered for the purposes of event scheduling - scheduling solely by one event per revolution would not give you much precision.

b) while Aspire has sequential injection, it squirts fuel into all cylinders simultaneously four times per camshaft revolution, so x4 time. Also the squirts are pretty long - while idle squirt would be around 3ms, while cranking stock ECU does around 15ms x 4 times per camshaft revolution, depending on coolant temperature.

I could not start my engines for the few days before I've realized that it is now colder and increased the lowest temperature fuel squirt duration to 20ms.

[AndreyB]

A moment of silence for the solenoid on the starter. Over the last 12 months, this solenoid has seen so much work as some solenoids see in their lifetime.

We will never forget the sacrifice of this hero solenoid. It's death would not be in vain!

[AndreyB]

I am not getting it - I cannot start a cold engine 20F/-7C cold. I have to use stock ECU, warm up the engine to some temp, and when it would fire up as a charm. I am just missing something I am using way longer fuel pulses - like 30ms long full batching, that's a lot for a 1.3 engine.

[kb1gtt]

What are you doing about spark advance? Often with electronic ignition, it will also multi spark at low RPM. Can you make it spark more than once during cranking?

[AndreyB]

What are you doing about spark advance?

I am trying to copy the stock ECU behavior. While cranking, stock ECU uses the shape of the CKP signal for spark - i.e. spark dwell is more like 20ms and not 4ms like it is while running, and the discharge point is the fall of CKP signal.

[puff]

an interesting remark from the workshop manual (might be off topic, but it's about increased pulse times!)

Engine fuel temperature sensor (EFT Sensor)
This is another resistive sensor. Located on the fuel rail it measures temperature of the rail rather than the fuel. The resistance varies with changes in temperature. The signal is used to increase the injection pulse time when undergoing hot restarts. When the fuel is hot, vapourisation occurs in the rail and bubbles can occur in the injectors. Increasing the pulse time flushes the bubbles away, and cools the fuel rail with fuel from the tank. The fault may not be evident to the driver, there may be a hot restart problem. The fault is indicated by illumination of the malfunction indicator light (MIL) on North American specification vehicles.

it might be you're overflooding the cylinders?

btw, I was thinking of obtaining a stroboscope before converting from mechanical distributer to electronic system.

[mivaol]

В этом варианте как понимаю всё работает по ДМРВ(MAF), вопрос где ты нашел тарировку датчика?

[rus084]

а по ДПДЗ (TPS) будешь пробывать?

[AndreyB]

MAF - вопрос где ты нашел тарировку датчика?

Нигде не нашёл. Я не знаю тарировки датчика, да она мне и не нужна - я работаю с датчиком просто как с источником сигнала, который растёт с ростом расхода воздуха.

а по ДПДЗ (TPS) будешь пробывать?

Нет, потому что у меня нет времени И не думаю, что скоро появится.

[mivaol]

MAF - вопрос где ты нашел тарировку датчика?

Нигде не нашёл. Я не знаю тарировки датчика, да она мне и не нужна - я работаю с датчиком просто как с источником сигнала, который растёт с ростом расхода воздуха.

А как тогда рассчитываешь массу впрыска? Просто на то он и маф что измеренную массу воздуха делим на AFR получаем массу топлива, производим нужные корректировки над ним и впрыскиваем.
Грубо я свой уже от тарировал, теперь в планах более точно составить таблицу думал может есть готовые решения.

[AndreyB]

получаем массу топлива, производим нужные корректировки над ним и впрыскиваем.

Никак не рассчитываем никакие массы. я не знаю физического расхода воздуха, да и физическую производительность форсунок точно не знаю ни я ни ты. У нас тут так много неизвестных в наших уравнениях, что я сторонник разумно-табличного подхода.

[rus084]

а зачем его вобще тарировать , если есть топливная таблица ?

[AndreyB]

Sold Will need to get a different test mule one I settle down in the new place.