VE Table
My VE table estimate using the estimator from the Megasquirt website:
[need to add table - it's not with me here.]
If anything, it's a little optimistic - which is no bad thing for a 1st attempt as it only means too much fuel.
etc...
A Lambda table has also been created, but obviously won't do anything until the wideband sensor is installed. Bought some bosses for the exhaust and lambda should go in this weekend.
Progress so far
Well, the car now runs, and it has taken me to work. Short 6 mile trip. Initial results are good. The fans come on when they should, the engine warms up at a sensible speed, hot start is excelent, the engine is reasonably smooth in operation, but could be better!
I got the wideband calibrated and turned on auto learning and this has done wonders for making the car work well. It's turned into a rather quick car now - but I still want more!
Bad points are:
- The coolant and intake temperatures are still a few degrees wrong (better than before, but still wrong) - Refined again now, and only 2 degrees "wrong" now at 60 degrees. I think I can live with this...
- The VE map is not at all refined, but is getting there with auto learning now turned on
- Idle settings are still very wrong - all help appreciated - now fixed
- Acceleration enrichment is not right - but is getting better
- Cold start is better than it was, but not perfect.
note
Keep in mind that the lambda table is always used in fuel calculations, but indeed _also_ for supplying the ego controller with target lambda values, be sure to fill it with sane values.
Thanks!
The reference table you created with VE estimator from Megasquirt site might be VE * Lambda, while ours is pure VE, it can be needed to divide the table you created by the lambda table you put to get an accurate estimate, however during the tuning session it is easily fixed.
It's definitely pure VE. I did check that. But it's going to need tuning anyway...
Fuel pump
Fuel pump relay has been connected. I'm using EC36 pin15 - P259 channel 5. I'm using 3.5 seconds for initial prime and it continues for a second after the engine stops. Unscientifically measured from the previous ECU.
Cranking and CLT warmup settings
It was cold last night (around freezing) so I took the chance to sort out cold start. A lot of fiddling later and it's acceptable, but not brilliant.
[ADD CONFIG ITEMS]
Acceleration enrichment
No idea what to do with acceleration enrichment right now. Can anyone point me in the direction of help regarding acceleration enrichment?
- Dont worry about this,first try to get running the car through the whole RPM range.You must have a basic VE table first,Than you can play with the numbers (on a warm engine),and see when is it best.You floor the throttle,with the same speed for 4-5 times ,and see what happens on the WBo2.Im currently using 0.2s accel time.I tried different numbers in the rate / value fields,and a linearly increasing (from bottom to top) is what im currently using.oh yes ,and use TPS based accel enrichment!
[ADD CONFIG ITEMS]
Idle Air Control
The idle stepped does something, but I'm not confinced it's right. I connected the 4 wires from the stepper to the A,B,C & D channels (on the EC18 connector) going clockwise round the motor looking at it from the connector end. What do I need to set the step sequence as?
Things I'd like some help with:
Idle afterstart RPM (added value?) - Value to add to base idle speed when the car is first started.
Idle afterstart duration (s) - the duration to do the above for.
IAC afterstart (steps per 160 rpm) - don't understand what this is getting at.
Max steps to extend - total number of steps the motor can do. I managed to shoot the pin out of the end of mine. Don't do this as they get stuck in awkward places...
IAC step sequence - Lots of things, depending on how you wire up your motor. Mine was 201. ie drive C, then B, then D, then A.
stepper speed (ms) - Speed motor moves at. ie time between steps. 0 ms is fast and can shoot the pin a long way (see earlier)
iac_conf RAW - no idea! something to do with raw hex config?
See the IAC section of: MembersPage/MarcellGal/EngineSwap/AirFeed for more info.
I think I've cracked this now. My stepper is an "anti-stepper" like Marcell's... It was operating the wrong way round - so no wonder I couldn't get a stable idle! Suddenly, when I filled the position vs temperature table in correctly (high numbers mean the valve is more CLOSED for me) it works a treat. The idle speed creeps up a bit (100 rpm or so) as the block warms through, but I can refine that later when I set up the PID control properly.
I removed the old engine wiring loom after the injectors were shown to work. This might be considered rash. Indeed it was, because it stopped the fuel pump and starter working! Even though they weren't supposed to be connected to that part of the loom!! It seems TVR re-used part of the Rangerover loom, including where the rangerover immobiliser plugged in. (This was bypassed for the TVR immobiliser) It took 3 hours in the cold and dark evening to trace the 2 all black wires I needed to reconnect as they were mixed in with grounds and all sorts.
Now the hazzard lights and heater have stopped working. I haven't even touched those systems! (Maybe a 2nd genboard to control the heater & stuff???)
I suppose the moral here is don't do anything like this if you need the car the next day!!
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