stumbles on cold start

[K Rob]

01' Camaro BTR Stage 4 cam 233/248 .630"/.615" 111.5+2.5
Cold start seems to be running extremely rich - any help would be appreciated !Tune1.hptkevinidle.hpl

[SiriusC1024]

The log is a hot start. Regardless, commanded EQ is correct here. Look at the values for Open Loop EQ and Afterstart Initial Adder. It supposed to be doing that. The only problem is you can't tell if it's actually .85 lambda because there's no wideband data to verify.

The correct thing to do is tune the airflow side of things. Looks like it's not quite there.

Turn on LTFT's btw.

[K Rob]

tune the airflow side ? can you be more specific - Thank You !!

I will turn on LTFT's.

[SiriusC1024]

Yes. Start by tuning the VE table. There are a bunch of threads on how to do this.

Personally, I'd ditch the MAF and run it in SD entirely.

[horsepowerguru]

tune the airflow side ? can you be more specific - Thank You !!

I will turn on LTFT's.

Go to goat rope garage and watch his Gen 3 videos on MAF and VE tuning. that should get you to where you want to be.

[K Rob]

Go to goat rope garage and watch his Gen 3 videos on MAF and VE tuning. that should get you to where you want to be.

Done

[K Rob]

Here are a couple cold start logs

[SiriusC1024]

Got the tune to go with the logs or is it the same tune?

[K Rob]

Same tune

I can get it startup with opening the throttle blade more but it idles way too high and the iac is zero as well.

[SiriusC1024]

See if this helps with the startup. Change the cranking VE. There's a few things going on, but try this first.

[K Rob]

I will and report back - Thank You !!!

[Alvin]

Same tune

I can get it startup with opening the throttle blade more but it idles way too high and the iac is zero as well.

This looks like a stock VE table. You are going to get a good result until that is dialed in and that cam may never get along with that size cam. Got to have a wideband with a cam that large too. The narrow bands and the fuel trims can drive itself too rich with a cam that large.

[K Rob]

That helped - current log attached

[K Rob]

This looks like a stock VE table. You are going to get a good result until that is dialed in and that cam may never get along with that size cam. Got to have a wideband with a cam that large too. The narrow bands and the fuel trims can drive itself too rich with a cam that large.

Okay - got to give it a shot - Thanks !!

[K Rob]

i opened the throttle blade to get it to start - iac counts are zero but it idles too high as expected - closed the blade to get somewhat desired rpm.

[SiriusC1024]

Looks like idle really stabilized after CL enabled. It was running rich during OL. Try the OL and idle changes in the attached file. Get to VE, which it needs, after idle is stable.

Also, IAC counts are a little high. Try doing this.
https://thetuningschool.com/blogs/ne...elearn-process

[K Rob]

Looks like idle really stabilized after CL enabled. It was running rich during OL. Try the OL and idle changes in the attached file. Get to VE, which it needs, after idle is stable.

Also, IAC counts are a little high. Try doing this.
https://thetuningschool.com/blogs/ne...elearn-process

I have done the relearn a couple of times already - hopefully with the changes you have made it will idle soon without opening the throttle blade excessively.

[K Rob]

Well this is the best startup so far - it fired right up, struggled the whole time it seemed but it never died. Pretty sure its still rich on startup.

Thank You for taking the time to help - current log attached !!!!!!!!

[SiriusC1024]

Should tune the VE.

Engine Diag>Airflow>Mass Airflow Sensor set MAF Freq Fail High to 0Hz
DTC's are already right. SES light will be on, but that's because of MAF 0Hz.
Engine>Fuel>Oxygen Sensors set LTFT to Enabled and Min ECT to 140F. LTFT Boundaries>RPM Lo=900 Mid=1400 High=2200.

Post a log with those setting applied. Populate more cells in the STFT and LTFT tables of VCM Scanner. Try driving around a bit.

[K Rob]

Should tune the VE.

Engine Diag>Airflow>Mass Airflow Sensor set MAF Freq Fail High to 0Hz
DTC's are already right. SES light will be on, but that's because of MAF 0Hz.
Engine>Fuel>Oxygen Sensors set LTFT to Enabled and Min ECT to 140F. LTFT Boundaries>RPM Lo=900 Mid=1400 High=2200.

Post a log with those setting applied. Populate more cells in the STFT and LTFT tables of VCM Scanner. Try driving around a bit.

Perfect will do - Thank You once again !!!!!!