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Help/Confirmation on Ignition tables

Posted: Sat Aug 29, 2009 10:02 pm
by Hybridizer
I'm working on running a freshly rebuilt USDM ITR. I have not run eCtune with this motor until now. I've worked out many of the little bugs but I've come up on a new one. It maybe just be a datalogging quirk but that is what I'm asking you guys for. The car is having a break up in the mid range of rpms in the 5K area. Seems to go away at higher RPM's I've noticed on my datalogging that my igntion table readings and my actual readings are not matching up. The actuals are bouncing from matching the table to 0 degrees. It bounces back and forth at all rpms even idle. Is this a normal effect to see in datalogging? Advice on what could cause it if not? I'd be happy to post a example of what I'm talking about. If it's needed. Thanks!

Posted: Sat Aug 29, 2009 10:55 pm
by xenocron
Post your CAL and LOGs

Posted: Sat Aug 29, 2009 11:36 pm
by Bugermass
Sounds like you have a bad distributor and the ECU is loosing sync.

Posted: Sun Aug 30, 2009 10:57 am
by Hybridizer
Here is the log and cal. This was the first time I took the car on the road. All that has really been done on the cal was leaned out the fuel maps a bit.

Posted: Sun Aug 30, 2009 1:34 pm
by 98vtec
if you have the stock honda ignition advanced turned on at all times, the table timing will NEVER be what the actual timing is. You have ignition correction tables that change the actual engine timing going to the engine as well. AT higher RPM in WOT, the timing difference between table and actual can be as great as 15 degrees!! Which is a pretty big jump and is a reason why the numbers in the tables are not what is important. I have my stock ignition advanced turned off after 650mbar. This gives me a good bit more control of the ignition timing and you will not see the big jumps in table timing and actual timing. When you have an advanced setup where the ignition timing will make or break the engine, it is imperative to have ultimate ignition control. so basically, what you are seeing is normal.

Posted: Sun Aug 30, 2009 1:43 pm
by Hybridizer
If you check the log though. I'm having a 30+ degree disparity. The fact that is happens across the range from idle on up is my question. I understand it's possible to have some but if you check the log, it seemed a bit extreme to me.

Posted: Sun Aug 30, 2009 1:47 pm
by 98vtec
ok i took a quick glance at your map. since you are just starting out tuning (i think at least), start by tuning with the 2d tables. its a lot easier to use as you can see the shape of the charts better. The graphs will typically be uniform. IE: if there is a jump in fuel at 400mbar/3000rpm, then there will likely be a jump in fuel at 500mbar/3000 rpm. The lines in 2d mode should NEVER cross. They can touch, but will never cross. Pay attention to your AFR in the overlay logger. (hint) - use your foot brake so you can hold a load on the engine and keeping the engine in the cells you want to be able to fix. while tuning, turn closed loop off (tune in open loop). If you plan on using closed loop, you can turn it back on after tuning. Your closed loop parameters need to be tuned in the 13.5 area because the job of closed loop is to remove fuel as needed to meet the target AFR. If you tuned part throttle/closed loop parameters too lean then engine will run all funky once you turn closed loop back on.

Posted: Sun Aug 30, 2009 1:53 pm
by 98vtec
wow ok, i see what you are saying now.....thats a bit drastic

Posted: Mon Aug 31, 2009 6:26 pm
by Hybridizer
I think I traced my issue down to a horribly done ecu pin job on the cabin side of the car. I have since been able to get my actuals to match my tables 100% of the time. No issues anymore. :)