lately i noticed when i mash the gas from a stoplight i get to about the rev limiter and the car starts to hesitate and stuble then a second or two and it continues fine. Now this doesnt happen when crusing. if i mash the gas at say 40 it goes fine.
i have a brand new fuel filter in there.

103000 miles
plugs and wires havent been changed
o2's havent.

 

High RPM breaking up is a very common opti symptom. Are you on the original, or if not how old is the one in there?? How old are the plugs and wires also?

 

i would say original everything. there is a slight hesitation at low rpms if i were to rev then engine, everything seems to be better the car is NOT cold

 

actually I believe almost redline break up is usually coil and midrange break up is opti...

 

yea i'm having the same problem, around 4.5k to redline it'll stumble and feel like you hit rev limiter and also if i rev to hard from idle it'll stumble then rev... unless it's at 1k or higher then it'll rev fine. also my car won't start when wet out. i had new wires, cap and rotor put on and it ran fine for awhile but now it started to act up again, but now it's kind of a hit and miss with it stumbling at full throttle in the higher rpms. i really need to figure out which part it is before i go replacing things seeing as i lack $$$. i've been thinking it has something to do with the ignition coil or the ICM.

 

If you haven't replaced the entire opti, then that is "your" problem...

 

hey guys i have the same problem except mine is from 4.5K to redline, and when you mash it anywhere under a bout 2000 it stumbles! im running 87 octane gas, at the moment and the problem is not as noticeable with higher octane, but is still there. the fuel pump/filter/fuelpressure regulater, opti and waterpump have all been changed resently, its a 95 M6 with 61,xxx on it, original wires though. any ideas?

 

now I know where thread hijackers anonymous meets....

 

well in your post above you said that almost redline breakup might be a coil problem, thats the only time my car backfires. and also when i first got the car back the little stumble if i revved at idle was non existant no matter how much throttle i applied then about a day later the little stumble came back and about a week or two later the high rpm backfiring came back and it wouldnt start again if it was wet out. sorry don't mean to be a pain in the ***, i'm just trying to get a better idea of what the problem is before i go dropping another huge *** load of cash into the car after spending 900+ for a tune up.

EDIT: oh yea, i didn't mean to hijack the thread by any means. i just figured that since this thread already exsisted that i'd ask in here instead of making my own thread. plus everyone would prolly tell me to do a search. so... sorry no intent to hijack, just to learn

 

I consider 4.5k rpm at the middle to top of midrange. Redline is 6k or so rpm, 6200 I believe is the rev limiter. Let me put it this way. From experience if you have break up at a certain rpm all the way to redline than I blame the coil. The reason being that the coil's ability is being maxed out therefore how can a coil perform better at a higher rpm than where it breaks up?

And, If you have any break up below that, but only at a certain rpm or range of rpm than I blame the opti.

And... Now the Simpsons are on, so I will be gone till 7... I thank you

 

aright thanks for your help, i guess i'll have to drop it off at the mechanic's next time it's supposed to rain so they can figure it out

 

I believe that the LT1 rev limiter is somewhere around 5750 give or take. You may be thinking LS1 when you said 6200 was the limiter.

 

No need for that yet. It wouldn't hurt to grab a new coil plugs and wires to do yourself. If the move to the opti comes, it's a very easy swap that should only take a beginner a day to do.

 

I have the same trouble with My 97 z. I have been trying to chase this down for over a year now. I has been a major pain in the a$$! I have replaced cap, rotor, wires, plaugs, pcm coolant sensor(which did help), and km for LT4. The miss is still there, but I have arise up high in the band from 4.5k to 5k. still looking!

 

Oh yeah, you are right about the rev limiter. It is 5750 on the lt1s, but I have rised mine up to 6250 with HP III.