Base Map From Scratch

[vr4scott]

I've searched high and low and can't seem to find exactly what I was looking for. My question itself is simple and I can expand on it, for my previous situation.

What checklist do you go by when starting a tune from scratch?

Obviously, one would go through the typical getting idle set, loading a stock timing map, setting global for injectors, etc. My problem previously was that in almost all of these, it requires the vehicle to be running. What do you guys do when it will barely run, if at all? Or even fire consistently?

This is what happened to me:

I basically took every nut and bolt out of my car and started new, from what was a relatively stock 2G. New engine, new trans, DW1200 injectors, 3" GM MAF, V3 and MAF cable, 6262, 272 cams, S90 TB, no ISC/FIAV, converted to all wheel drive, painted the car, 2GB conversion, tucked the engine harness, eliminated emissions, relocated the fusebox, removed/cleaned/replaced all grounds, etc.

I made sure everything was assembled correctly, cams degreed, boost leak tested and everything was ready to go, or so I thought. Loaded all stock settings on the ECU, set the global for the fuel, didn't know what deadtime to start with so just guessed 350, selected GM MAF, etc.

I could never get the car to stay running without throttling the pedal. Where do you guys go from there? It took months to get someone that tunes to come over to my house. He messed around with the airflow sliders and some other stuff, got it to fire and stay running. We set the idle as best we could, went for a drive, and he tuned it good enough that I can drive back and forth to work without much hassle. It accelerates and cruises smoothly when driving "normal". It surges once or twice then dies when coming to a stop if I don't keep my foot on the gas, I have to throttle it to ease it into a steady idle around 1100 RPM, and WOT amounts to sputters/backfires but RPM will continue to climb. At least the car drives now so I can take it to a dyno when time/money becomes available for a proper tune.
I was thinking about this earlier and I have no idea what he did to get the car to run, and it's driving me nuts.

How do you set the idle on a car that won't run by itself?
How do you calibrate a MAF that you have nothing to compare to?
How do you set deadtime when you don't have a known starting point?

These are the kind of questions that are bugging me and it doesn't seem like there is a cut and dry (that I've found) answer to how to approach a tune from scratch, I basically get "you just do it" or "I just messed with some settings".

 

[CABLODSM]

The sputter as you accelerate sound likes plugs..

What's the gap/brand

 

[hotrodssnova]

When your car dies coming to a stop, sounds like the rolling idle setting needs increased. As far as injectors and dead time go, contact the manufacturer. They can give you that information. I have had to adjust my dead times in the idle area due to cams.

 

[GST with PSI]

You should never have to start from scratch, since as you inferred, Mitsubishi already did that for you. You should be able to make some slight changes to the stock tune and get the car running fairly well. If you're unable to get the car to idle, I suspect you may have underlying issues

Post up a log.

 

[Seamus]

Now adays the only people building maps from scratch are the ecu engineers and OEMs. Even on standalones the user or tuner is able to import maps they have or are available for similar vehicles.

the days of tuning a an old haltech from nothing with obtuse injector values are over.

to think people use to send maps by floppy disk in the mail! Probably seems crazy to you younger guys.

 

[keltalon]

I have seen very few people remove the isc and the rest of the idle control and have success with getting the car to run correctly.

 

[vr4scott]

The car is good to go now. I was inquiring just for future reference what people do from the start.

 

[keltalon]

The car is good to go now. I was inquiring just for future reference what people do from the start.

Thats what I like hearing Congrats!!

 

[bmxfelon420]

Yeah all I had to do to get my car running was set the injector settings and MAF type. The car started and ran pretty well right away, I had to adjust the base idle and stuff but that was it. As long as your injector settings and base timing and all that are right, it should fire right up.

 

[vr4scott]

When I first started, it would just crank and crank and fart. If it started it would immediately die. You could keep it running by throttling it, but it just ran like crap.

 

[lil corb]

When I first started, it would just crank and crank and fart. If it started it would immediately die. You could keep it running by throttling it, but it just ran like crap.

It sounds like it had some settings totally off and not in the same city let alone ball park of right numbers. As long as you plug correct numbers and check correct boxes you should of been able to somewhat drive the car to fine tune more.