scoob22

I just bought a 2009 Cobalt SS/TC a couple of weeks ago, and this past weekend I was using the no-lift shift. The check engine light flickered but never stayed on during my shift from 3rd to 4th. Then I tried from 2nd to 3rd no-lift shift, it started to miss while the check engine light came on and it remained on. I pulled codes and the codes said cylinder misfire. Seven different codes came up cylinder misfire and was saying all cylinders. I changed to factory plugs, gaped at 32 and I repeated it and it done the same thing. I was just wondering if this is the tune causing the problem and has anyone had this problem.

nobody2u

The tach can lag when you are modded/tuned... you sure you're not shifting too late and hitting the rev limiter?

scoob22

thats what im thinking. what normally happens when you hit rev limiter

themacguy

Quot from Trifecta:

If you haven't read the article on*no*lift*shift, read that first:*http://www.wot-tunin...ift-nls-anyway/


Many people have reported misfire problems when attempting to*no*lift*shift*after installing an aftermarket tune.**The reason this happens is because most tuners remove the boost pull-back at high RPM to improve performance.

Per the article on*no*lift*shift, the factory tune has to prevent over-revving with about 15psi or less of boost at the rev limiter.**Aftermarket tunes may raise this to as much as 22psi.**Because the ECM uses a combination of fuel and spark cut to prevent over-revving, the ECM has to intervene much more aggressively to prevent an over-rev with 22psi running through the engine vs. 15psi.**This can cause misfires.

There are two ways to solve this problem if it happens:

1.**We can re-instate the boost pull-back at high RPM
2.**The driver can stop using*no*lift*shift*
Like This
- Vince
Owner, Trifecta Performance Inc.

scoob22

what is the best suggestion to do?

1 re-instate the boost pull-back at high RPM
2.driver can stop using*no*lift*shift

YelloEye

iTrader: (3)

IMO just don't NLS. You're not gaining a whole lot on the stock turbo by doing a NLS, it's back at full spool before you know it. NLS isn't exactly the healthiest thing for your valvetrain anyway.

themacguy

Number 1.

scoob22

who can i get to re instate it?

strazdice

iTrader: (1)

Where are u located? And you'll have to do is look on the dealer map and find one cloest to u, otherwise i agre with the fact NLS isnt worth it neat to have but i've never used it not even when racing, btw its also the same if u shift normailly then to use nls, i think nls was like a tenth faster or something or slower dont remember

themacguy

I might have added some confusion here.

#1 if you want to NLS.

My personal advice is to go with #2.

user 72239

iTrader: (4)

I wouldn't NLS when tuned. You are asking for problems

scoob22

Yeah i believe im goin to stick with not using NLS

scoob22

I think it may end up tearing something up..... really isnt much difference in it maybe a second but my car runs great really happy with it just had this problem didnt know if the tune caused it or what!

skip_jones

sounds like you are hitting the rev limiter. you need to find out if he upped your
RPM limits. what are you shifting at? you need to start your shift about
400-500 RPM before your limit. at stock rpm limits, shifting at 5800 works
perfect. gotta shift quickly too.

soundjunky

iTrader: (4)

if you bounce of the rev limiter, rockers can pop off.

just ask around

jacream_booSSted

this