LQ4 starts and dies cold. will not idle

[oleshp]

Hi everyone, I need some help.

I am very new to tuning at all but have an understanding of how engines and other vehicle systems work (I have been working on cars professionally for about 20 years).

I now have access to HP Tuners at this job and would like to learn to be proficient using it.

Now onto the problem,
1971 Nova with what Im being told is an LQ4 in it. It is a customer vehicle. When its cold, will start and die unless you give it a considerable amount of throttle to keep it running. Everything mechanical seems to be functioning properly from what I can tell. As I said, I have very little knowledge of ecm tuning and I don't want to go tweaking things and mess up the tune that's in it.

Can someone please point me in the right direction and help me justify my boss getting hp tuners?

Attached is the current tune, a log of the start/stall (3 attempts), and the list of mechanicals

thanks nova LSx ZERO.hpt nova startstall.hplnova specs.jpg

[edcmat-l1]

First thing is, what injectors are in it? Name brand and size.

Second, you need to be logging more pids than you are.

Third, it would be better if you could keep it running and post a longer data log. That way we can see how far off stuff is.

Use this channel config and get another, longer data log. Keep it running and slowly let of the pedal and see if it will idle.

P01 DBC.Channels.xml

[2xLS1]

So you don’t know anything about tuning yet you are turning for a customer. SMH.

[oleshp]

As I said, I have a good understanding of engines and even tuning with carbs, just not using hp tuners. The vehicle is already tuned by someone. I’m more just trying to learn what’s wrong with it and see if it’s something I can fix relatively easily. I have to start somewhere.

[oleshp]

The only information i have on the injectors is the numbers on them which lead me to believe they are 42#. I don't know the brand and neither does the owner of the car.

edcmat, the layout you sent doesn't show when I got to "open layout" in vcm scanner. Am I doing something wrong?

I appreciate your help and patience

[gtstorey]

And what is the part number on the injector.
Tuning Lesson 1: In GM tuning, injector data is all important and is far more than just flow rate.

[oleshp]

The number on them is 01d030b. I wish I knew who built the car in the first place, but unfortunately, that?s all the info I have on the injectors.

[gtstorey]

Search on here for 01d030b shows those as crappy injectors without correct data.