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Yanoo_
27-03-2012, 11:19
Could anybody tell me the pulse width of the Williams (stock injection system) at 900, 3000 and 5000 rpm?

kj16v
28-03-2012, 00:53
Depends on several factors: manifold pressure, air temp, water temp, battery voltage, and lambda correction.

Yanoo_
28-03-2012, 10:38
Depends on several factors: manifold pressure, air temp, water temp, battery voltage, and lambda correction.

at 900 rpm: idle, closed butterfly valve, warm engine (coolant temp approx 85-90 C), ambient air temp approx 15 C (intake air temp ~40-45 C), manifold pressure: IIRC ~350-400 mbar, battery voltage 13.9-14.1 V, lambda correction: closed loop, lambda voltage approx .500 V

at higher rpm: constant vehicle speed, part throttle (half throttle ~ 128-130 unit in XR25PC), warm engine (coolant temp approx 85-90 C), ambient air temp approx 15 C (intake air temp ~40-45 C), manifold pressure: don't know, I could not save the log file :( battery voltage 13.9-14.1, lambda correction: closed loop, lambda voltage approx .500 V

kj16v
11-04-2012, 10:47
I can tell you the raw values in the oem Williams map, but I can't remember the calculation to turn them into approximate pulse widths. At idle its around 74-80

and at the cruise conditions you mentioned it really does depends on the engine speed, but somewhere between 96 and 145

What is it you need to know the pulsewidths for?

Yanoo_
12-04-2012, 20:07
I can tell you the raw values in the oem Williams map, but I can't remember the calculation to turn them into approximate pulse widths. At idle its around 74-80

and at the cruise conditions you mentioned it really does depends on the engine speed, but somewhere between 96 and 145

What is it you need to know the pulsewidths for?

I've run a diagnostic on my car. All values were appropriate except the ISCV's value (it was a bit higher than the desired / given in the user's manual) and the injection time / pulse width, I quess it was a bit low (IIRC 1,5 msec at idle). Despite the lambda voltage was around 500 mV at idle and at constant vehicle speed (half throttle, 60 kph), the real fuel consumption was high (it's always a bit overfuelled, usually it's ~ 9-10 l / 100 km), but the calculated consumption was suprisingly low (6.4 l / 100 km). I quess the injectors are leaking and the O2 sensor doesn't work properly.