MembersPage/PerVolvo (2013-11-20 20:07:51)

13-11-2013

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).

Does this engine have EGR valve ? (looks like an oversized IAC valve).


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.

Triggerlog1 http://www.vems.hu/files/PerVolvo/crank%20at%20-2%20dg%20outside-1.triggerlog

Triggerlog2 http://www.vems.hu/files/PerVolvo/crank%20at%20-2%20dg%20outside-2.triggerlog

vemscfg http://www.vems.hu/files/PerVolvo/camsync%205.vemscfg

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.

http://www.vems.hu/files/PerVolvo/trig%2058-59.triggerlog