question about Leganza Ignition Timing

AntDX316 · Post by **AntDX316** » Sat Jul 05, 2008 2:12 am

this is a question with out my new starter installed

well i set my 1000 or 1500RPM on the apexi neo to -50% then i started the car and it seemed to sound real weird like not enough fuel is being fed or something basically a stuttering idle well now the car wont start

everytime i try to start the car and hold it the radio and clock turn off completely the headlights dim a bit and the fuel pump makes noise like it turned off and turned back on but the car just wont start but makes the cranking sound

will i be sure once the new starter is installed it will start properly?

is the cause of a too much ignition advance or retard? does the ignition advance or retard only when the engine is moving or does it automatically set it self when set to the on position and or while cranking? is there anyway to reset the camshaft position manually?

Post by **PrecisionBoost** » Sat Jul 05, 2008 7:01 am

So why do you have your Apexi NEO at -50%????

You say your not getting enough fuel but then your cutting fuel with the Apexi right?

So wouldn't pushing that back to zero make it run normally?

Not sure about your starter issue... sounds really odd... if the engine is cranking then there is no issue with the starter.

Timing doesn't come from your cam shaft..... it comes from your reluctor wheel on your crankshaft

Basicly as you crank the engine it waits to see a spot where there are no teeth (only one spot on the entire wheel ) then it automaticly knows it's exact position.

Because the crankshaft rotates twice for every ignition event on one rotation it will be the power stroke for cylinder #1.... then the next time around it's the power stroke of #4

So... given the crankshaft sensor can't tell if cylinder #1 or cylinder #4 is in it's power stroke it uses an additional sensor on the camshaft.

The car can run without the camshaft sensor but it is right only 50% of the time ( the other times it guesses wrong and the engine doesn't run... or it runs very poorly )

So that's the basics..... on a DIS ( distributorless ignition system ) you don't have the ablility to change ignition timing

In short the engine will automaticly set the ignition timing to roughly 8 degrees before top dead center and attempt to start the engine.

After the engine is running then the ECU can change the timing by advancing it to make more power.

xiaogary · Post by **xiaogary** » Mon Jul 07, 2008 4:45 pm

Hi thread owner, sorry to disturb the thread. I have some questions regarding cmashafts and timing as well to consult the experts here.

Hi PrecisionBoost, can you help me on the camshaft advancing? My knowledge is limited. Now I have 285 cams on my DOHC engine. How do I advance the timing?

When you say advance timing, do you mean advance the electronic sparks timing (using piggy back ecu) or advance the camshafts lobes displacement using adjustable venier pulleys such that the intake and exhaust valves are opened earlier and closed later.

I faced some idling lumpy issue before I went for tuning, but after tuning, its better and smooth. However, my tuner told me, I could gain more power with venier pulleys since I have higher duration cams now. Also with venier pulleys, will the engine run even more smoother? I need to step some trottle whenever the rpm is below 1.5k, or else, its quite lumpy/choppy.

Also with lighten flywheel now, sometimes when I clutch in too fast, the rpm drop very fast until it almost reach zero and engine dies off. My mechanic asked me to approach the tuner to increase the idling rpm. Will that help? Is it possible to increase the rpm with the UNICHIP thats currently installed in my stroked and bored Aveo 1.7DOHC?

Maybe we can discuss more at my thread here:

http://www.daewootech.com/forum/viewtopic.php?t=10529

Once again, apologise to the thread owner. Sorry.