tuning an m30 with large injectors

[mitch5]

I have my own thread for my turbo build but i figured that a separate thread would be more useful since alot of m30's run large injectors. Right now i have 80lb seimans deka high z injectors and am using msextra 3.3. I cant get the car to run stoch. without lowering the req, fuel to 1.4 ms, ts calculates it to be 4.7. I know you can adjust the ve table but im lowering it to 15% and its still pig rich. I have the car running open loop and i have all accelenrichment turned off. I just pulled the plugs and they are black, while inspecting them i found the gap to be .1, that sure doesn't help. im very new to this and i must be missing something any help is appriciated.

[Xenocide]

Maybe afterstart enrichment or warmup enrichment are turned on? I've been out of the game for awhile, that's just a WAG.

[T_C_D]

Starting with the appropriately sized injectors would have been a good idea. 42lb are good for 400rwhp.

[mitch5]

Starting with the appropriately sized injectors would have been a good idea. 42lb are good for 400rwhp.

That's true but I do see my self eventually pushing this car past that. Should I just lower the req fuel lower than what ts suggests

[TotiTurbo]

I'm using the same siemens deka 80lbs with VEMS and I'm idling fine (~13-13.5:1) at 4.5ms req fuel and the ve table is around 55-60% at idle if I remember correctly, spark plugs gapped @ ~0.4mm (~0.016")

[mitch5]

I'm using the same siemens deka 80lbs with VEMS and I'm idling fine (~13-13.5:1) at 4.5ms req fuel and the ve table is around 55-60% at idle if I remember correctly, spark plugs gapped @ ~0.4mm (~0.016")

That sounds more reasonable, there must be some warmup setting or something that I missed that's causing me to get so much fuel.

[bornagain]

I suggest posting up an msq and a datalog, that will tell a lot more about your situation then mere speculation

[mitch5]

I will post one soon once I get the car running again. This car got but on the back burner.

One thing I have noticed is that on my innovative lc2 wide band the megasquirt reads the afr but the gauge just reads 10.8 and doesn't fluctuate

[Shadow]

I have those semen injectors ass swell, idle is fantastic.

They idle noticeably better then the old greentop 42# that where in there.
I guess because they react faster. Those old metal ones you get used, on a tight tight budget.
I think my deadtime with those were 1.69 something like that.

req. fuel. 4.40
alternating 2
dead time 0.840

Is this your first time tuning?
Get it up to operating temps then start adjusting idle and deadtime.
It doesn't have to idle at 14.7 afr. Is that what the m30 does stock?

[mitch5]

This is my first time tuning, along with my first time building a circuit haha. Thanks for the settings, my dead time is at .9, the default setting in ts. I have tried changing the settings after the car is warm but that didn't have any effect. The one thing i could see being a potential issue is the clt sensor, i have noticed that it reads about 20 f higher than ambient, this is assuming the coolant is ambient temp after the car sits for days. I know the mega manual showed a table for calibrating but i havent been able to fin that option in tunerstudio. Im not worried about getting the car to idle at 14.7, just something higher than 10. The only time i accomplished this was lowering the req fuel, seems the deadtime might help.

edit i just found where to calibrate the temp sensor, im asuming the 325i senor is the same as m30?

[Lurker27]

Tune your dead time. Dead time error scales with injector size and is pronounced at low duty cycles. I run 72lb low z with no issues, and passed emissions

[mitch5]

So im back at the car again after taking a break, im at the point where i fully understand tunerstudio but still cant get my car to have a reasonble afr. I have wue off and ase. i have a 3.5L so my req fuel is 4.7 ms, my car runs so rich to the point where the ve bin is set to zero and the car still is rich? this is just at idle because when an engine load is put on the car leans? Can you guys running the 80lb injectors send me your tune so i can compare the settings?

[Shadow]

When VE is set to 0 and it doesn't respond that's not the injectors something is very wrong.
My friends volvo did this. His injector circuit was fried. MS3 fixed that though.


Take a screen shot of your injector settings so people can better help you.
Don't make use work, we don't care enough.

[crispy]

If others are getting those big ass injectors to idle well, is your fuel pressure too high? Why not just run smaller, more appropriately sized injectors until you do go for more HP that needs 80lb injectors?

[mitch5]

We'll I feel like an idiot, my vaccum hose to the map gauge wasn't fully connected. I noticed that after driving the car and seeing that the map pressure wasn't changing. Now I'm taking it easy in the car until I get my new temp sensor. Megasquirt was telling me my car was running at 230f when the temp gun I have read 177 at the rad. Still I figure I might ass swell finish up all the wiring