Random NON-smooth acceleration..
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From: Central Illinois
Random NON-smooth acceleration.. I'm just now finishing up all of my kinks and bugs from the h/c swap. I have new gmpp opti, new plugs/wires, and new msd coil. I got a new racetronix fuel pump and 30#svo's. The car when it accelerates extremely smooth 3k+ rpm's and just normal below that.. (speaking of WOT.) and when it's pulling smooth like it should, it pulls alot harder. But when it isn't pulling smooth, it is "rough" i guess is only word i can think of to describe it. It just doesn't pull as hard like it should be. I got it dynotuned. I dunno really what to think.. I mean it could be fuel, ignition or something that I havn't even though of...... Any suggestions are appreciated, I just kinda wanna know what to look for first.
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From: tampa
your description wasnt the best. does it feel like its bucking? misfiring? are you throwing codes?
i would pull plugs to see if any stand out. that would show if one cylinder isnt quite on par with the others or if it has been misfiring, etc.
i would think that would be a tuning issue. possibly with partial throttle AFR issues if its fine at WOT.
i would pull plugs to see if any stand out. that would show if one cylinder isnt quite on par with the others or if it has been misfiring, etc.
i would think that would be a tuning issue. possibly with partial throttle AFR issues if its fine at WOT.
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From: Central Illinois
Sorry for the crap description. It's all at wot. Just randomly doesn't accelerate smooth. I'll floor it and it pulls, just not near as hard as when it's smooth.. I don't have any codes thrown. It's hard to explain what it does.. I may jsut take it up to my tuner and have him drive it see what he thinks....good 2.5 hour drive unfortunately though haha.
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From: tampa
Sorry for the crap description. It's all at wot. Just randomly doesn't accelerate smooth. I'll floor it and it pulls, just not near as hard as when it's smooth.. I don't have any codes thrown. It's hard to explain what it does.. I may jsut take it up to my tuner and have him drive it see what he thinks....good 2.5 hour drive unfortunately though haha.
So what you saying is: At WOT
-your car accelerates inconsistantly, sometimes smooth the entire RPM range, sometimes rough below 3k RPMs, but always smooth above 3k rpms.
Right?
Ive had similar problems on two separate occations. One would randomly accelerate rough the entire RPM range, realy it would feel like it was pulling a house. That problem ended up being a bad connection on the knock sensor. The other time I had problems more similar to what i think your describing, and it turned out to be the opti harness that had a bad connection. Or at least the problem never happened again after I changed it.
You might try and post up in the regional forum and see if someone can do a datalog for free. You might ask if someone has datamaster or a similar program.
-your car accelerates inconsistantly, sometimes smooth the entire RPM range, sometimes rough below 3k RPMs, but always smooth above 3k rpms.
Right?
Ive had similar problems on two separate occations. One would randomly accelerate rough the entire RPM range, realy it would feel like it was pulling a house. That problem ended up being a bad connection on the knock sensor. The other time I had problems more similar to what i think your describing, and it turned out to be the opti harness that had a bad connection. Or at least the problem never happened again after I changed it.
You might try and post up in the regional forum and see if someone can do a datalog for free. You might ask if someone has datamaster or a similar program.
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From: Central Illinois
It's normal(normal being kinda rough) until 3k then gets extremely smooth at wot once it gets past 3k. And when it decides to randomly not to be smooth after 3k then it just accelerates "rough" through the rest of the acceleration, it's usually when i just mash it, rather than ease into the acceleration. (Roll races when I mash it.) I'm gonna check the connections tomorrow and see what I come up with. Thanks guys.
