VEMS 1.2.18 install to standard Volvo 960 B230FT with camsync (sequential) and Crane HI6 CD ignition.
Original Volvo 60-2 VR flywheel sensor
Volvo 740 Hall distributor on camshaft for camsync
AW71 auto gearbox.
Running firmware 1.2.17 for 1 month, and now 1.2.18
Try to improve fuel economy, which is lousy (8,1 km/l mixed) with original ECU.
With VEMS, now running 9,5 km/l mixed driving, but still tuning it.
EGR : exhaust gas recirculation
Many factory engines recirculate a small amount of somewhat cooled exhaust gases into the intake at part load (cruise).
- might help a bit with emissions
- increases MAP somewhat, and decreases "pumping losses" (==drawing in air through a significant pressure drop across the almost closed throttle) and therefore slightly improves fuel economy
Does this engine have EGR valve ? (looks like an oversized IAC valve).
- if yes, is it PWM or stepper type ? (how many pins, what resistance ?)
- Do you plan to use it ?
- relying on EGO correction only (less fuel despite the higher MAP), or also some anytrim ?
- if you find that under some static cruise (perhaps in a temporary setup) the injector pulsewidth can be reduced significantly (eg from 4 msec to 3.6 msec) by some EGR-valve setting, than it might worth to apply some fw-mod for that strategy (in some ways similar to the tank-evaporator-canister purge valve, which is also enabled at certain part-load situations, enabled gradually, and dumps to the intake manifold).
Thanks for the EGR tip. Have not thought about that.
My engine has no EGR, but a 2 wire PWM valve operating at 100Hz (Volvo 940 standard freq).
I have no plans for a EGR valve, (have not seen any 940 in DK with EGR) but right now I am experimenting with hot air inlet at cruise speeds to try improve economy. At cruise I bypass the intercooler letting hot air (35-45 degrees) into the intake. I don't know if this will improve economy, only time will tell.
20-11-2013 Help needed
Engine cannot start when -2 degrees.
Engine gets more and more difficult to start the lower the temperature.
VEMS takes 8-12 sec to send IGN pulses out to Crane HI6 when +8 degrees outside.
VEMS will not send IGN pulses out to Crane HI6 when -2 degrees outside.
When or if the engine gets started, other start attemps the engine fires up after 4-6 sec.
When warm no problems starting.
I can see the IGN pulses from the VEMS on Crane HI6 LED indicator.
Battery is 65 Amp/h and new.
The problem is that VEMS do NOT send IGN pulses out when cranking in cold wheather.
Look at the logfiles. If you mark between 2 missing tooth VemsTune says 59-61 tooth count, but if you count them manually there is 58 tooths.
The logfiles are from cranking today at -2 degrees.
If I disable camsync, still no starting.
The wierd thing is if I disconnect the camsync sensor and disables camsync the engine starts.
After that I can reconnect the sensor and reenable camsync and the engine starts.
But tomorrow when it is cold same problem I guess.
It seems to me that the camsync sensor can disturb the crank trigger signal
In this triggerlog with engine idle, VemsTune reports 58 and 59 tooth count, but when I manually count them there are 58 tooth counts.