ok so i am really getting to know my utec really well now. i love it!! dont get me wrong....


now what i am wondering is we all have had times when we floor our car and it doesnt respond correctly. dataloggin shows that for some reason the stock ecu retards the timing and adds fuel cause it runs really rich when this happens.

from my understanding. with open loop fueling, the UTEC reads what the stock ECU is going to do for fuel and adjusts according to that. i have recently had my UTEC outta my car for overnight (24-25 hours) and now my car runs really really crappy. it was running great with high 12s AF ratio. hooking it back up today and it starts at 11 to 1 and ends up 10.2 to 1 by 5000.

now i know when you reset the stock ecu, there is a learning curve where it needs to "learn" your mods. now i understand with MAP based fuel with the FI its totally controls the fuel according to MAP.

is there anyway to fully override the stock ECU running naturally aspirated?? i wish i could just throw the stock ecu right out the window. this computer related, car running like crap, problems are "driving" me crazy..

i am going to drive around my car for another day or two and see if the computer acts normal again. if not then it is back to the drawing board.

any comments or suggestions from anyone who truly knows and understands the utec would be great!!!! thanks guys!!!

 

I admire you for tuning your own engine. Couple of things. Read the manual about 4 times cover to cover. You will be surprised at the stuff you pick up after a couple of re-reads.

Second, open loop fueling is not offset fueling. If you want to tune the car via simple MAF adjustment, then open loop fueling needs to be disabled. If you want to tune in open loop fueling mode, then you will be setting the injector pulse width across all the load sites. The stock ECU, in open loop fueling, is completely out of the picture (except in the 0% load column), and will not change your tune....ever. That's your job now.

 

thanks, the reason i am doing my own tuning is so i can fully understand what is going on and when i change something on my car i want to be able to retune it all by myself. i will get it down. i figured with the open loop fueling originally it would fully take over control of the fuel map. i drive around and data log ALL the time to try to learn about the engine more. the problem is "those few times NA" when you floor the car and it doesnt respond the way you want, something effects the UTEC also. i am trying to figure out "exactly" what is causing that, so i can get rid of it

i can drive around and do a couple WOT runs, 5 of them will be perfect and there is always one time that the car doesnt respond well. when i am datalogging, for some reason the stock ecu is retarding the timing to around +14 to +15 degrees.... now i wouldnt care about it with the UTEC except for whatever it is make the UTEC adjust things two where it doesnt run right

as stupid as it sounds, (i hate this mod more than anything too) i am thinking maybe its some grounding issue. it seems like its some electrical problem and every once in a while i am having surges of electric through my dashlights and so forth


PS i read the manual every day, seriously, and every day i learn more things.... Naturally Aspirated, what should my open loop fueling TPS and RPM thresholds be at?? 60 TPS and 20 RPM??? thanks guys!!!!

 

audible, if the UTEC is registering 14 degrees of timing, this has nothing to do with your stock ECU. Once you hit the 10% load column, the UTEC takes 100% full control over timing. If the timing in the map, is different from what you are logging, its likely due to the knock feedback kicking in, and retarding timing across the board. Each gear is going to hit slightly different load sites, so its important to check them all.

 

Just a little OT, but where can I read up on the UTEC, and where can I get one?

 

You can learn more about the UTEC, or purchase one here: http://www.forgedinternals.com/store...cat=273&page=1

You can download the instruction manual from here: http://www.turboxs.com/utec350zupdate.htm

 

i reflashed it and it is working incredible. my car has never pulled like this, i am gettin 12.9 to 12.3 from 3000 to 5000 and then it gets really rich, i am just trying to get it all stable. i really need to order the tuner wb so it will log it all at once and make this much easier to do... hehehe

not sure what was the deal with it before but the utec was doing some weird stuff. cant wait to get to the track next wed for some NA and N20 runs!!!

 

You mean you RESET the ECU, you didn't reflash it right??

 

no i reflashed the utec and started all over, i am thinking that i have figured out a little problem with the utec and NA. see with the MAF pull down option it "tells" the stock ecu that there is different voltage coming from the MAF so it will add or decrease the fuel to the injectors. now when you reset it and there is a "learning" curve my car was running really bad. i have been taking out the utec and adjusting it in my room via 9v battery and i think that when i took it out for a while the stock ecu was reseting itself. so now when i take out the utec, i plug in the stock ecu while the utec is outta my car and it is working wonderful now....

now sharif, i know with speed density mode, you fully override the stock ecu with the fuel map, but with the MAF pulldown, arent you just adjusting the signal from the map sensor, but the stock ecu is still firing the injectors. So the problem with this is .... when the car is in learning mode?? when the car isnt warmed up enough?? when the car is getting some code and running bad?? it is actually just adjusting the "limp" signal from the ecu

sorry for the novel. i just love learning everything i can so i can share my knowledge with anyone who asks....

 

I have been learning alot about the UTEC aswell, have not had any issues with it like you described. But i agree, the more people that learn the more knowledge that is shared. Just take baby steps

Later
Aceman

 

now i just need to figure out where my car is making the most power, i guess i will map a couple different maps. tune it for 13.1 12.7 12.4 and 12.0 to 1 and get on a dyno and see which map is the best for my car, it seems like high 12s AFR is where my car feels the best NA.

 

I have a question. Can you hook up a laptop and just pick the map you want, based on where and how hard you want to drive?

It would be cool If you were driving around the city, you could use an economy map, and if you wanted to really unleash the car's power, you could pick a more aggressive map.

 

its actually way better than that, you have a switch mounted where ever you want with 5 maps that you can choose from, on the fly as long as the car drops below 1600 rpms

 

*phile salivates.

 

This is absolutely correct. But when you refered to open loop fueling in your opening post, I assumed you were running open loop fuel fueling, rather than MAF pulldown.

You can easily tune an NA car with MAF pulldown...works just fine. As you mentioned, you are essentially doing +/- fuel at the various load sites, rather than setting the injector duration times.

 

can you run open loop fueling naturally aspirated???


if so that is what i will be doing tomorrow. i would love to bypass the stock ECU...

i guess what i am wondering, can you run speed density NA???

 

Open loop fueling can be setup as with MAF based, or MAP based...you pick. So yes, you can run open loop fueling mode on an NA car, as long as you select "MAF" for the load indicator. Just a word of caution. When you switch to open loop fueling mode, the ENTIRE fuel map needs to be populated with something, or else the car wont run. It's a time consuming process, the first time around, but once its done, the level of control is amazing.

 

thats my problem, i have been tuning open loop fueling this whole time... thats why i was getting weird AFR and everything, i have got it all figured out now though and have my AF 12.8 across the board. i have it MAF based and it seems to be working well....



now... sorry, i have it open loop fueling but i dont have it on speed density. do you have to have it on speed density and have all the values in there. is that what you are talking about ??

 

How comprehensive is the manual? Does the manual have everything you need to know?

 

the manual tells you about everything it does... but it doesnt explain in detail everything it does.