Very cool!
Location: Missouri
Posts: 191
My VIN: 10715
Very cool!
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
I put the Volvo idle motor in and so far I only had to increase the delay one switch setting. I did discover one thing I need to change but don't think the idle motor change has anything to do with it.
What I saw today was like a sticking return of the throttle plates. It would drop fine if I punched the throttle but if I let off slowly it would hang up around 1300 RPM.
What I think my problem is the advance is still on and not letting the idle drop to my new 1200 RPM setting where I turn the advance off. You would only see this if you remove the idle switch. So I think I need to turn the advance off when it drops below 1500 RPM just to make sure your idle returns to normal.
It maybe that I just need to reduce the curb idle with this new idle motor but I still think the safe thing to do is change the advance RPM.
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
My beta tester is getting good results now. He installed a different idle motor and downloaded my latest software. Now we are just looking for bugs and minor adjustments to the software.
I'm getting ready to try added the "AC bump" into my car.
There is another thread about idle hunting. Just an FYI on how my ECU may prevent hunting caused by the OEM idle ECU. It will not fix hunting caused by the lambda ECU. As I stated in that other thread, if you increase the delay before you make an idle adjustment it should prevent ECU caused hunting. I did choose a longer delay with my unit and the end user can adjust that delay with four choices via a DIP switch on the board. I was able to run the shortest delay with the OEM idle motor and not have any hunting. With the Volvo idle motor I'm running the next delay (little bit longer).
So with the slower close loop response time, I have to have it faster when you take your foot off the gas and the engine RPMs drop. I detect when RPM is falling past 1500 RPM and instantly load the last good idle value that held the idle correctly. This results in no undershoot of the set idle speed. It just drops cleanly to the idle speed and holds it there. The other condition is going down hill in gear below 1500 RPM. Well just like the OEM unit, my ECU also closes the idle motor fully. So my software loads that same correct value instantly when the RPMs are below the (set idle speed - 100 RPM). So you do see the idle undershoot in that condition but it recovers so quickly unless your looking for it on the tach, you will not notice.
Last edited by Bitsyncmaster; 06-30-2011 at 10:51 AM.
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
Just added an LED flashing code to display to the user what Revision level the software is at loaded into the ECU. The code flashes one time after you turn the key on and don't start the engine. You don't need to wait for it to flash only if you want to read the code.
I did this because I plan to offer field updating to the latest software.
Now the user will be able to tell if his unit has the latest code.
The first released code will be Revision #1 so you would see one flash.
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
I hooked up the AC bump wire. Pretty easy to do. Just connect (splice) to the pink (mine looks light brown) wire on the diode on the right side of your relay compartment harness.
I'm going to include this wire that will have a one terminal connector on it. I will drill a hole in the center of the connector housing and install the wire.
I was not going to do this on my car but I'm going to keep another calibration table when the AC is on so you should never have any engine deceleration problems (undershoot). Just ran down to the bank and was sitting in a long line for the drive up and the AC keep me cool sitting at idle speed. I have the normal RPM set for 800 so when the AC is running it bumps it up 100 RPM (900 RPM).
Location: Fort Lauderdale
Posts: 4,740
My VIN: 02613
Club(s): (DCF)
Perfect!Originally Posted by Bitsyncmaster
Great work as always!
Farrar
3.0L, automatic, carbureted
Location: Fresno, CA
Posts: 1,133
My VIN: 3997
When the units are done, are you planning on including instructions on how to install the ECU and how to tune it correctly?
Living The Dream Since 2005 - VIN#3997
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
My web site already has the instructions. It's a work in progress document.
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
Well I'm really excited with something I came up with on my latest software. My new change will really make it hard to get into that mode where you get an undershoot of the set RPM value. Even though I've got that mode working very good in that it recovers so fast you would only see if you were watching the tach for it.
First, as I found I have to turn the ignition advance off below 1500 RPM. If you turn it off lower than that you risk your RPMs won't drop enough to control. This only takes effect if you remove the idle switch and diode so I'm controlling the advance.
I now close the idle motor fully above 1200 RPM. I keep the idle motor closed until RPM drops to the set RPM value +100 RPM. Then it instantly loads the correct value that is recorded in the calibration table. This works perfectly with the AC off but I think I may move that +100 value up to +150 so with the AC on it won't dip any. The AC causes the engine RPMs to drop faster than without it.
So to get into that one undershoot mode you can only do it by not running the RPM above 1200.
Last edited by Bitsyncmaster; 07-03-2011 at 03:49 PM.
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
It took loading the idle PWM value at 300 RPM above the set idle speed to stop undershoot when decelerating with the AC running. So now I have to work my software to do this. This is running the Volvo idle motor which I think is slower so it should work better with the OEM idle motor.
Last edited by Bitsyncmaster; 07-06-2011 at 07:12 PM.
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Dave M vin 03572