Ok as some of you know i have an 05 2.2l that's turbocharged, i have had issues with lean trim codes since i got done my build, i have been all over this thing and there is no vacuum leak.
I have seimens 42lb injectors with a cavalier eco harness and am tuning with trifecta. These injectors are shorter than my original ones and i have never liked the way they set in the fuel rail. I have a wideband and my afrs were lean at idle, then low 11's in boost and the car runs great anywhere but at idle. Vince has been working around the issue and got the fuel trims to settle at idle, but i am still getting a lean trim code. The car also idles at 1100 rpms and takes fits of fluctuating up and down. This has been going on from day one, AFTER i put in the 42's and loaded the tune.

I had my original injectors in and the stock tune, fired the car up with the turbo setup in place and it idled normal, no issues.

The car runs awesome but i am tired of fooling with it, everyone says #60's suck at idle. So i don't know what to do, Vince is willing to keep tuning with the #42's until we get it right, but i am tired of the B'S, just need to fix it and move on, i bet i have flashed my car25 times, lol...

FYI, t3/t4 turbonetics 50 trim, boost is set to 7lb, but about to go to 9lb and stay there.

 

25 times aint ****.

tell you tuner to step up there game, trim codes are all derived via maf calc.

he's got it wrong.

 

get 60s then you wont have to upgrade later it will be worth it

 

Well, he's no rookie as far as tuning is concerned, not saying the problem isn't in the tune. I'd be happier knowing we were not tuning around a problem with these injectors. Thanks for the input though....

Well i don't plan on going much further than the 9lb spring, but who knows. I just want to know my engine is getting the fuel it needs when it needs it...

 

have the 60''s in my supercharged setup.... i met you at carisle mine was the black cobalt......hey when your car is idling bad what is your battery voltage at

 

Yea, you were at the dyno, i remember. I've never payed alot of attention to my battery voltage, why do you ask?

How do the #60 injectors work for you?

 

yeah i would not drag the boost out 2 far on stock internals ... idk even what that bottom end will hold or the block witout crackin or tossin a rod.

if ur battery voltage is low it can cause ur pcm to be slow and react slower... adjusting to a/f ratio slower making it run lean because its adjusting to late or earley... ( kinda a guess but thats how it would work in theory) so pritty much low voltage=slow pcm=slower injector fire.... fix geting higher rpm=more voltage( spinn alternator faster)= faster pcm because of more voltage=faster more responsive injector fire.


could be rong but i would beleave this to be right... or atleast on the right track.

 

Well this is not a bad theory, but the pcm is designed to operate on 12 volts, not necessarily charging volts of 14v, so i would'nt expect this to be a problem. I do have a voltmeter i can look at, just haven't paid alot of attention to is since this issue arose. I usually run around 13.8v@ idle...

As far as pushing the stock bottom end, i'm not intetionally trying to blow it up, but i do know it's a possiblity....

 

the only time i noticed my afr go lean if my battery voltage goes below 13.8 since are cars alternators are pcm controlled they have different charging rates....they sometimes go into some kinda of charging mode ferget what it is called but the battery votage goes down to 12.8 which is normal for are cars to do but are cars don't like it if they have bigger injectors to get around this you can tune your car a little on the richer side for idle so if the volts do drop it doesnt go too lean or you can fool your pcm by turning on your rear deforster or turning on your headlights....and by the way i love my 60's also just ran a 9.07 at the track with a 1.8 60ft running 11 pounds going to run it again with the smaller pulley to see what that gives me.....hope this helps

 

^^ woah woah
did you just say you ran a 9.07? is this the eighth mile? i am hoping


and i would say throw 60s in, you will be safe with them you KNOW. hell i am runnig them on a stage 2 pulley.

 

Good info, i'll look into this, i believe we had it tuned pretty rich at idle but the pcm was still wanting to add fuel and showing lean trims. Vince said he had to add alot of injector voltage offset to fix the issue,,. Now we are getting close at idle, but i am still getting the lean trim code. My car is also idling at 1100 rpms now,it used to be around 800 rpms. Not sure on that either. I cleaned the throttle body, and it started doing the high idle right after and has never went back to normal.

 

my 42's are working perfectly.. dont know what your problem could be.

 

my stage II injectors are working fine on my 2.2, i have a 06 circular shape fuel rail, not the squarish looking one, and yes they were shorter than stocks, but still idle and run fine

 

your sig says you have #79's


I have the round fuel rail too, i don't know what the deal is with these, driving me nuts, lol...

 

Well the computer is not always going to end up getting the right AFR when you set it up, especially with the different injectors. The shorter injectors is a big deal as well, because it means less ends up in the cylinder and more ends up on the walls, which can lead to your lean code your getting....as well as the resistance of the injectors might be different than the ones you had and your computer doesn't know that, since the computer reads the injectors based on an ohm resistance of the current coming out of them.

I wouldn't upgrade to the 60# ones and would think about downgrading back to stock...gas prices are going up again...

 

Going back to stock is not going to happen, i'm not to worried about gas prices at this point, with this car, it doesn't even get driven much. I do think you have a point with the shorter injectors not getting all the fuel into the cylinders, especially at low pulse width applications. The thing is other people with 2.2l's are running the same injectors and not having the issue i am so i don't know, maybe defective injectors or something....

My computer has been tuned to run with the 42's, these are the same injectors gm uses on there stg 2 kit for the ss/sc, i've never ohmed them but that's a good idea too... Thanks for the input.

 

yes i do. i just did a test to see how everything was working with my boost motors going in withen 4 weeks to get built and retuned on the 79s.