Tuning problems at 6-7k

[livedsm4g63]

So i have done a bunch of tuning and im running into an issue. i have been running sorta lean so i thought my 190 pump was going out. i then changed it out with a walbro 255. as you can see i am now running 10.4s almost all the way untill 6500k.
At that point its like i am back firing. as you can see my tables are all messed up due to it running so lean with the last pump. i pulled timing and as you can see i can go no further so i tend to think i am pulling timing and it isnt doing a darn thing and that im just tuning around something. maybe coil... but when i think back fire i think to much fuel that is unburned. any ideas would help a bunch. thanks a lot!

just to let everyone know my set up. big 16g, stock maf, 3 inch exhaust, intake, and 950's which are a total over kill but nice to have for the future. Boost gauge is reading between 18-19 psi.

and another weird thing. there is another dsm in my parking lot that is doing the same thing. but not mod'ed as much.

 

[ADrewzki]

There's something wrong with your setup obviously. There's no reason you should be adding 14% more fuel at 6000 rpm just to retard timing. I'm not seeing the 10.4:1 AFR you claim in your original post. I see your AFR jump around a lot due to the amount of fuel you're dumping in. Do you have a fuel pressure regulator for your walbro and 950cc injectors? I'm also not sure about your fuel settings. Your profile states that you have FIC 950cc injectors but your fuel settings are not correct. For 950cc injectors, your base setting should be -53% global with a dead time of 315us. You have -45% which sets you up richer to begin with. Fuel tables.

I'd start by getting a regulator and setting that up correctly for a 1g. Then set up your fuel settings and fuel trim settings correctly. In my opinion, having a MAF that works correctly and is not hacked is a plus.

Good luck.

 

[livedsm4g63]

see i just looked at my global as well and realized that it has to be at -52.6 (or -53) before i made the log. meaning if i set it at -53 it will lean it out. so if you were to look at my tables, i could set it for -53 but then of corse my sliders would max out even more. so to me that doesnt make much sense. i could be looking at it wrong though.

as far as the maf is concerned, i do have a gm maf sitting around i just have to oder the translator. and i havent had time to order an fpr yet.

 

[ADrewzki]

I'm curious to know what your log looked like before with global of -53% and deadtime of 315us. You are running rich. Your LTFTs are both negative by about 5%. Why did you change your deadtime so much anyway? Did you buy your DSMlink off someone?

 

[Rob10_99]

Start simple, have you checked plugs?

 

[livedsm4g63]

plugs are good, checked them and they are gaped right, they were a little white because of running lean with my old pump, but now they are looking good.

and i did buy dsmlink off someone else with those settings already on it, and i had no problem running it, and i did change my global lastnight and it was super lean so i actually backed out because my wideband was reading 12.4's on the gauge and i didnt want anything to let go. i however did not change my deadtime. lowering the dead time would make the injectors on more so therefore it would richen it up? ill go out today and do another log with -53 and 315us and see what i get.

something is just telling me it may be the coil. i will be checking that as soon as i get time.

 

[ADrewzki]

plugs are good, checked them and they are gaped right, they were a little white because of running lean with my old pump, but now they are looking good.

and i did buy dsmlink off someone else with those settings already on it, and i had no problem running it, and i did change my global lastnight and it was super lean so i actually backed out because my wideband was reading 12.4's on the gauge and i didnt want anything to let go. i however did not change my deadtime. lowering the dead time would make the injectors on more so therefore it would richen it up? ill go out today and do another log with -53 and 315us and see what i get.

something is just telling me it may be the coil. i will be checking that as soon as i get time.

You have some large concept errors. 14.7 is considered stoichiometric for our cars. 14.7:1 (air:fuel). You are not running lean if you're running 12.4:1. That's still rich.

Basically the problem I have is that you claim you're running lean when you are at 10.4:1 in your first post and now 12.4:1. You're trying to run your car based on settings that were already on another car. It's like trying to get your car to run right when your base timing is f'ed up and all you have to work with are cam gears. It's retarded. Set your global values and your deadtime to the values they should be and start tuning from there. Make sure your timing is set correctly at idle with the car warmed up. Start with a goddamn baseline and maybe you can figure out what the hell is going on. Hell, pull the ground off the battery and let the ECU reset and start from scratch. If the idea of adding 14% fuel at 6000 rpm doesn't seem remotely wrong to you with your mod list, then you have some self-education that needs to happen.

 

[livedsm4g63]

lets just say i really hope you didnt tune your car... you can go ahead and aim for 14.7 at wot but ill bet itll last a couple pulls before saying i told you so. turbo'd cars aim for 11.5- 11.7 to run safely at wot.

and i know my fuel looks messed up, thats what im trying to explain...along with my timing. something doesnt seem right. because i take out timing and add fuel but im still hitting fuel cut or im backfiring.. I think you need to have some education in general

Hell, pull the ground off the battery and let the ECU reset and start from scratch..

i have a 1g. do you know anything about dsm's?

 

[ADrewzki]

lets just say i really hope you didnt tune your car... you can go ahead and aim for 14.7 at wot but ill bet itll last a couple pulls before saying i told you so. turbo'd cars aim for 11.5- 11.7 to run safely at wot.

and i know my fuel looks messed up, thats what im trying to explain...along with my timing. something doesnt seem right. because i take out timing and add fuel but im still hitting fuel cut or im backfiring.. I think you need to have some education in general



i have a 1g. do you know anything about dsm's?

You didn't explain that you logged a WOT run and got 12.4. You said your wideband read 12.4 and you were lean. Period. That makes no sense by itself but it makes more sense now. I guess I should've assumed since you didn't provide a log. For what it's worth, I generally tune for 11:1 so I agree with you on that and 14.7 is stoich. Not what you should tune for on WOT but the statement does hold true.

Are you telling me pulling the ground off your battery does not reset your ECU? Is your version of DSMlink different than my v2? The reason why I suggested that is because it seems you've been having your problem for some time and your car may have some odd STFT and LTFT values that it's trying to work off of. Resetting your ECU will set those all back at zero and give you a base starting point.

Don't get upset because you don't include all the necessary information in your post. It's difficult to put things together when I have to guess what's going on.

 

[livedsm4g63]

im not mad at all, from my logs at the top you can see that it is a pull. and not a crusing log. im just trying to figure out whats going on. when im crusing around its all good, only when im at wot is when this happens.
just makes me wonder what it could be.

and to let yah know 1g ecu's can be unpluged and nothing is lost. as far as 2g's everything will be reset.

 

[sb7775]

You need to zero everything out and start over. Read jeffgst.com on getting things calibrated. You need to use the correct deadtime and global. Once they are set you never touch them. FIC950 use -53 330, not -45 435.

Steve

 

[JeffGST]

i have a 1g. do you know anything about dsm's?

Why post a statement like that. You will only create an unproductive argument with remarks like that, especially when you are the one who is wrong.

When you disconnect the battery from a 1G, you do not lose the saved settings in DSMlink, but you do reset the long term fuel trim values. All of your LT fuel trims are maxed out negative. You have a ton of work to do.

As for your lean condition at WOT, it is just PLAIN OBVIOUS why you are running leaner than you should be. Look at your BoostEst values, compared to your actual boost level. The ECU thinks you are at 15 PSI when you say that actual boost in the log was 18-19 PSI. You have done nothing to the upper airflow sliders in order to calibrate and fix this issue. Read up on my site and educate yourself.

 

[livedsm4g63]

Why post a statement like that. You will only create an unproductive argument with remarks like that, especially when you are the one who is wrong.

When you disconnect the battery from a 1G, you do not lose the saved settings in DSMlink, but you do reset the long term fuel trim values. All of your LT fuel trims are maxed out negative. You have a ton of work to do.

As for your lean condition at WOT, it is just PLAIN OBVIOUS why you are running leaner than you should be. Look at your BoostEst values, compared to your actual boost level. The ECU thinks you are at 15 PSI when you say that actual boost in the log was 18-19 PSI. You have done nothing to the upper airflow sliders in order to calibrate and fix this issue. Read up on my site and educate yourself.

thanks for the pointers

So i went out tuning for a couple hours lastngiht and this morning and i came up with a rough tune. my fuel trims seem to be set and my global and dead times are set correctly. i also went ahead and set my boostest at my psi which is 17psi. some things of concern

i cant seem to lean it out past 4k which i would assume, boost leak. wideband drops to 10.4. so its not maxing out because my max low is 9.8

im still knocking at 6.5k, but this time it wasnt a backfire it just knocked.

and if i was to have a boost leak, is that why my BOOSTest goes downward? because at the beginning of the pull its fine at the correct MAFraw 1600HZ. however as im later in the pull i could read the same 1600HZ but my BOOSTest drops (to about 9ish).