Help with first wasted spark project

[hybrid]

If your O2 sensor is configured right, it looks OK when it finally runs, but it goes very lean just before it stops in your log.
Also, if you are having to use throttle to get it to start, then you're either too rich on cranking, or you need to open your idle valve a bit more on cranking.

[rickb794]

Changing the spark output may damage your coil if it is not right. I believe you were directed to look at the input to see if the polarity was reversed or you were capturing off the wrong edge which would cause the timing to change when rev'd in fixed mode.
Also the timing has to be checked and readjusted after changing those settings.

[Tonyorlo]

I remember watching the gauge as it was running. It was more on the rich side while idling. I need to set up the AFR guage better, I only went in and selected the correct gauge, I did not put any time in calibrating it. I most likely need to open the IAC more during cranking Like you mentioned Hybrid.

I spoke to Matt from Diyautotune, he said using the resistor spark method requires spark output to be going low. I will say after that change the timing worked correctly. I did have to adjust the #1 tooth angle to make it work correctly.

I had the cylinder heads off the engine before I made the change to megasquirt. I want to eliminate the possibility of the problem being mechanical rather than electrical, I am going to double check the valve lash. Right now thats what I think the problem is.

For the FIDLE to tach mod, can I place a pullup resistor externally on the harness?

Thanks alot for the help! Im slowly learning this stuff

[hybrid]

Ok, you definitely need to calibrate AFR table to make sure your O2 sensor reads right, or you'll never tune it properly.

[Tonyorlo]

I checked the valve lash and made some adjustments. I did forget to calibrate the AFR untill after I did the data log. The engine will fire for a second and shut off, It will not stay running. I have played with cranking pulse and idle every which way I can think of with not much luck. Any suggestions?

[hybrid]

14 AFR is probably a bit lean for warmup.
Have you tested that your idle valve is working?

Your VE table looks very strange. You might be better off putting it back to the factory table.

[Tonyorlo]

I will pull the IAC tomorrow and verify it works.

The VE table is the one that the generator made up. It definitely is not right, I hoped it would at least let me start it though.

[hybrid]

You don't really need to generate that table. Except to get the min/max axis values right.
The factory one will work as long as you have your Rqd fuel and other basic settings right.

[Tonyorlo]

How do I go back to the factory one?

http://www.megamanual.com/v22manual/vetable.

Using that program it makes a table way different than what the one in tunerstudio made.

[Tonyorlo]

Well I tried to tweak my VE table myself. I got it to run and idle. Not very smooth though, and its definitely running rich. I almost don't know if I can believe my AFR gauge, but I was idling in the garage so that will make it seem much worse. I cheated and used the tune analyze live, it made suggestions which did make it run better. The tune definitely needs work though. Any suggestions?

[rickb794]

Always start tuning with the hot idle, get the motor good and hot. Thermostat must be open.
Make sure you are out of any trim areas WUE ASE etc.
You should not be using any of these for hot idle, and you cant tune a cold motor.
You tune a hot motor and then adjust the trims to get it to run cold.
To tune idle first disable closed loop idle control. Set idle speed manually
Disable O2 correction, & always tune on a fully warmed motor.
Add 1 or 2 degrees in the spark table below your target idle speed.
(this will help the motor recover from a sag, especially automatic trans)
Check that WUE ends at no less than 100% and at a temp slightly lower than tstat opening
Make all the cells used for normal idle (a square of 9 cells) in the lower left of your VE table the same number.
Start the motor and adjust the throttle stop so the motor will run steady 700 - 900 rpm.
Then highlight all the cells in the lower left corner, and use the up or down arrows to change them.
Adjust to make the motor happy not shooting for a specific AFR.
(many try to set at 14.7, few if any motors will idle there)
You want the smallest number that provides a smooth stable idle (lean best)
Note the AFRs in that area and change your AFR table so Auto Tune does not change them back.
(I lock out those cells when using Auto Tune.)
Another reason to adjust the AFR table in the idle area is O2 correction will try to steer AFRs in that direction
Then you can make final adjustments to the individual cells to fine tune.
Always make final tuning adjustments on a fully warmed up motor (thermostat open).
Then if auto put trans in gear and fine tune again (different cells).

Now you can enable closed loop idle and return the throttle stop to just barely open.
I set the throttle stop to just barely open because gack from the PCV will collect around the blade opening and close it up over time.
Not closed so far it sticks (if using closed loop idle).

All of the other adjustments use the hot idle settings as a base and modify them for different conditions.
Now once a day you have the chance to make observations for altering WUE settings.
Also cranking squirts and ASE

[Tonyorlo]

I let the engine run and get to operating temp. I played with the VE table and idle control, so it would run on its own. When its warm it fires right up. I took it up and down the street a few times, its clearly down on power and I am getting a backfire through the exhaust. I let VE tune analyze run when I was driving to help get the table closer. I followed your directions Rick, it all helped a lot. Now I just need to spend time working at it to get it dialed in. I will include a current tune and datalog of the run.

Thanks!

[Tonyorlo]

I am having problems with the stepper IAC, is there a way to test the IAC outputs with a multimeter? I want to verify they are working so I can then verify the IAC works.

[ChevelleFan]

You should be able to go into the CanBUS / Test mode menu --> Output Test Mode (Idle Valve) and test it from there.

Also, from your previous post about being down on power, your AFR table is very lean -- 13.0 at WOT, 17.5 in cruise areas. You might consider richening that up a bit.

On the Basic/Load Settings --> General Settings, if you set Incorporate AFR Target to "include AFR target", your VE table, once dialed in more thoroughly with VE Analyze Live, will be come a true VE table, and you can then easily adjust rich/lean just by changing the AFR table.

-Dave

[Tonyorlo]

Dave,

I tried the test mode in CAN bus with no luck. I played around with the IAC settings win no change either. Should I see 5v on the IAC outputs in test mode?

I have since richend up the areas around idle, and the AFR gauge shows about 13-15. I can't get my idle below 1300 because of the IAC. My gauge is off from the tunerstudio, I have changed the ground to the sensor ground so hopefully that fixed the calibration problem. Once I get the IAC figured out I will change the setting to include the afr target.

The engine idles ok, but if I crank the throttle open quick I get a backfire. I can gradually open it up without the backfire. I am worried there is an ignition problem. When I go to WOT quick there is some black smoke coming from the exhaust so I know the AE needs tweaked as well as the table.

Thanks for the reply!

[hybrid]

Have you verified your timing on the crank with a timing light?

[Tonyorlo]

I have verified it during cranking and while running when the timing was set to fixed. I am now running it off of the table, I need to watch it with the truck running to make sure it looks ok.

I was missing the jumper between js9 and s12c, after installing that the IAC works. I think it needs some adjusting, but it's 11pm and my truck is a little loud for me to play with this late. I mess with it tomorrow after work.

Also after grounding the AFR gauge on the sensor ground it syncs up much better with tunerstudio.

[Tonyorlo]

Took the truck for a drive. Using VE analyzer its getting much closer. I am still getting a backfire during increases in the throttle. Its definitely down on power too, and kinda sluggish under acceleration. I do have a problem, I ran out of fuel on the drive, and after refueling I am down to 50psi fuel pressure. It always maintained 58psi, its a walbro in tank pump and a LS1 vette filter.

I did verify the timing and it seemed to be ok. Ill include a datalog from today.

[Tonyorlo]

I may have found the problem, I hope so atleast. I have the injector staging set up to simultaneous with 2 squirts per cycle. Should I try 1 squirt per cycle or 2 squirts alternating?

[hybrid]

When you say injector staging - do you have two sets of injectors staged at different times?
Or you just mean the setup of the regular injectors?

Mine is set up for 4 squirts alternating on my V8.