Steve's Megasquirt/tunerstudio Help Thread

[bmays]

I didn't have much time to look through your tune but from my glance at your datalog, I noticed you have a pretty high Acceleration Enrichment. If it was me, I'd probably look at the Accel Enrichment table (TPS based) and decrease those values a bit. Use like 1/4 or 1/3 of what they currently are and see if it helps make it a bit more crisp.

I appreciate it! I actually just stuck a really rough AE value in so I could drive around the neighborhood for that log.

Even with the AE disabled my stumbling issue persists. I will drop that AE value down for sure though and see what happens. Thanks for the quick reply!

 

[a91what]

I appreciate it! I actually just stuck a really rough AE value in so I could drive around the neighborhood for that log.

Even with the AE disabled my stumbling issue persists. I will drop that AE value down for sure though and see what happens. Thanks for the quick reply!

a decent starting point for AE is to use double your idle pw for large tpsdot values and half the idle value for low tpsdot value

 

[a91what]

Thanks.Figured it out. Everything is set I believe.I did another 10 minute run in idle this morning

The overly rich AFR we see in the beginning of the log is from the WB being at 0V until it comes up to temp, TS reports it as the lowest value in your calibration. This is normal.

The Terrible cold start oscillation is caused by a lean condition I did what I could with the tune to try and clean this up. can you screenshot your WB calibration on tunerstudio for me? On my end I see 15AFR being your upper range value.

Try this tune and report back.

 

[twohawks777@cox]

The overly rich AFR we see in the beginning of the log is from the WB being at 0V until it comes up to temp, TS reports it as the lowest value in your calibration. This is normal.

The Terrible cold start oscillation is caused by a lean condition I did what I could with the tune to try and clean this up. can you screenshot your WB calibration on tunerstudio for me? On my end I see 15AFR being your upper range value.

Try this tune and report back.

RPM is a little high. around 1100. Still getting some oscillation on cold start and at idle.

 

[a91what]

Yup as i thought, i changed quite a few idle settings. the car should high idle until it comes up to running temp (180*) this is normal. In the tune you sent me your timing was set to a fixed value of 12*, i changed it so the car will run on the timing table, until we get the idle fuel correct with the car fully warmed up this will not get corrected.

Step 1 will be to get a good log of the car idling with a few throttle blips fully warmed up the cooling fan should be running if it is electric
* Tune the car with this log file *
Step 2 Cold start the car dont touch anything this will let me start tuning the warm up enrichment
tune the car
Step 3 drive car get log tune repeat

 

[Blown88GT]

Picture time

My afr table on my current build with 10psi on 93octane. this timing table is my normal tune with no Wmeth, I use table switching to add 6* while the meth is spraying. I could probably add more with the meth but I want it to stay together. %baro is the same scale as KPA

Your Ignition Table (203kPa) does not reflect the same amount of boost as the AFR Table (175kPa).
Why do you have a 9000rpm column?

 

[a91what]

Your Ignition Table (203kPa) does not reflect the same amount of boost as the AFR Table (175kPa).
Why do you have a 9000rpm column?

Don't get caught up on the upper AFR row, if you want everything above let's say 5psi to be 12afr. you can set your last row to be 12afr at 135kpa everything above it will be 12afr this keeps you from wasting resolution in the lower areas.

I have a 9000 rpm column because I can, rev limit set to 6500. Again don't let this get to you lol, it's just the way I set my tables up.

 

[twohawks777@cox]

Here's step 1 :
Step 1 will be to get a good log of the car idling with a few throttle blips fully warmed up the cooling fan should be running if it is electric
* Tune the car with this log file *

 

[Blown88GT]

Don't get caught up on the upper AFR row, if you want everything above let's say 5psi to be 12afr. you can set your last row to be 12afr at 135kpa everything above it will be 12afr this keeps you from wasting resolution in the lower areas.

I have a 9000 rpm column because I can, rev limit set to 6500. Again don't let this get to you lol, it's just the way I set my tables up.

Doesn't that waste resolution, too?

 

[a91what]

Doesn't that waste resolution, too?

Which part?

 

[a91what]

Here's step 1 :
Step 1 will be to get a good log of the car idling with a few throttle blips fully warmed up the cooling fan should be running if it is electric
* Tune the car with this log file *

Not at my tuning laptop, was this taken using the newest tune I sent?

 

[twohawks777@cox]

Not at my tuning laptop, was this taken using the newest tune I sent?

Yes, it is the newest tune you sent. Ran the car for about 25 minutes per your instructions.

 

[a91what]

Yes, it is the newest tune you sent. Ran the car for about 25 minutes per your instructions.

Will send updated tune later tonight.

 

[Blown88GT]

Which part?

2nd

 

[a91what]

2nd

I could have set it to 7k but 9k got popped in there and I left it that way. Either way I would need a column after 6k to cover fuel just before the rev limit.

Most tunes start with a 12x12 table I use 16x16 tables so already 4 extra columns and rows ahead.

 

[a91what]

Here's step 1 :
Step 1 will be to get a good log of the car idling with a few throttle blips fully warmed up the cooling fan should be running if it is electric
* Tune the car with this log file *

This is your old tune file. Please be sure you are posting the tune file that the datalog was taken with, this makes things confusing on my end.

 

[a91what]

I altered the tune using the log file you posted. all in all for a rough in it looked half decent lets do another round of warm idle testing with some free revving and rev and hold at a few rpm points.

 

[Blown88GT]

...Most tunes start with a 12x12 table I use 16x16 tables so already 4 extra columns and rows ahead.

For MS2: Only the VE Table (Fuel Table) can be set to 16x16. 12x12 is an option.
For MS3: VE & Ignition Tables are set to 16x16, AFR is 12x12

 

[twohawks777@cox]

Ok. I think I got it right if not please let me know what I am doing wrong. Thanks, My bad for the confusion. Newbie mistakes. lol

 

[stanglx2002]

I have a question in regards to the PWM idle valve (IAC). Can someone explain what increasing or decreasing the Valve Frequency does?

I have a weird issue that I have been chasing regarding idle. My idle control algorithm is set to Open-Loop, and with the tune being the same I get two different idle rpm of one being around 811 and the other 850 (these are averages over a few minutes) The AFR ratio is higher on the 811 rpm, which makes sense its getting less air and more fuel and the 850 rpm one is perfect. Of course, I am chasing the 850 rpm target as it gives a perfect smooth idle even with an E303 cam. The idle issue doesn't change during driving at all it stays the same the hole time. The idle s is a random idle issue too meaning that I can drive the car 3 times and the idle be at 811 and then the next time you drive the car its at 850.

Today I drove the car to work and it was perfect at 850, but yesterday it was at the 811. It is not due to headlights or voltage draw since both of those days where the same as well. This got me thinking that maybe its the valve frequency or the valve is going bad.

Any feedback would be great.