ok guys just saw a cobalt running turbo with out tuning, drove it around, no limp mode, rev it as high as 4000rpm, so limp mode, i have gotten limp mode b4, so i know i coulndt get past 3k b4 my car shut down almpst all its power, how is it it can sustain boost w/out tuning?
ps-his thread is on the 2.2 section

 

At a loss I think is what you were goin' for there!

 

some cars can. my buddy has an eclipse with a turbo and never tuned, n he runs 5 psi. after about 4k though he bogs horribly. i can beat him with my 2.2 with an intake. but, idk. its dumb though to run without tuning. totally stupid.

 

yeah he didnt rev past 4kish, im thinking car hit limp after that..not sure

 

I don't know, but don't do it! BOOM = BAD!

 

I bet the spark plugs are WHITE

 

i've never heard of an official limp mode for 2.2's

no/crappy tuning is one thing

the only time I've ever had my car lose all its power and throw CELs is when I had faulty nitrous wiring...

 

*edit* never mind

I have a friend here with a 2.2L cavlier that has a turbo setup. He uses bigger injectors and no tuning. Dude pulls high 12s in the 1/4 and has put 60k miles on the setup. Don't ask me why it has lasted so long, but I know the long version of the science behind it.

Reason it idles: The car will do WHATEVER it can to try to get itself to idle, regardless of the bigger injectors.

Reason it pulls like an ape: When he floors it the bigger injectors dump enough fuel in to compensate for the lack of a tune. Instead of commanding a proper 11.8 AFR it commands a 13 and ends up with like a 10.xx because of the fuel injectors not being compensated for like they are at cruise/idle.

 

is that my car ur talkin about

 

yes sir mr silent

 

lol...yea she idles fine ...but im boosting real low right now....like 1 pound...im playing it safe you can say but ill bump her up to some more once i get my exhaust done mayb 4~5....once i get tuning ill bump her up to about 8~9 pounds...then it will be fun...but already i can feel the change...i love it....she pulls hard....and since its automatic....my boost stays constant until i left off the gas.....

 

No offense but thats really stupid to not have ANY tuning at all. Get a AEM FIC and tune it, then get a reflash from vince that just takes away the governor and PE Delay. Then your golden, you can retune whenever you want.

Oh yeah, you will go into limp mode if the fuel trim is off by +/- 10(it may be a little higher though). My car would go into limp mode sometimes in first gear because i would be at like 50% throttle and it would rev so fast the ECM was seeing too much change in the fuel trim and it would throw it into limp mode when it was cold.

 

its all good man...i know its not the best way but i just had to install it....ill get tuning as soon as i get back from vegas...so no worries...the car will be sitting for a while.....im just driving it to and from work right now....and well 2morrow is my day off...so ill probably install my turbo timer and wideband sensor

 

how did you pull off 1psi? the turbo you have is internally wastegated, the lowest setting i have seen is 7-8psi, howd u get 1? i dont think boost controolers can loswer the boost lower than what the wastegate is set too