DVSWS6

iTrader: (17)

I had a similar problem, but the car would stutter (sp?) cruising on the hwy. No codes either. These were new O2 sensors, but a local speed shop hooked up a data logger and was checking the read back off the O2 sensors in real time. My driver side was way different than the passenger in millivolt readings. Can't remember the actuall number but it was obvious. Changed to another new one and car ran fine ever since. See if you can get someone to read your O2s real time, because new isn't always "good". Just a suggestion...

WS62000

iTrader: (21)

Checked for a vacuum leak, but there was none. So, even though they are brand new O2's, check them out again?

Viper

iTrader: (6)

Absolutely. I chased O2 problems for almost 2 years, went to the Bosch O2's and have never had an issue.

WS62000

iTrader: (21)

So how do I go about checking just the O2's?

DVSWS6

iTrader: (17)

You need to find someone or some place that can hook up to your diagnostic port and readback info from your O2s in real time. Maybe the tuning guys can chime in here if like HPtuners or Ls1edit has real time data logging. I think the guy at my local speed shop was just using a professional/mechanics OBDII scanner, but it was displaying the millivolt readings from the O2 sensors in real time. At idle I want to say one was like 5ooish millivolts and the other was like 900ish but jumping all over the place. I can't really remember the exact readings though. It was like $40 to figure out one of my new AC Delco O2s were bad and to delete air, egr, and rear O2s. New Bosch ones from Checker and no hesitation/stuttering since.

VB112

i had the same problem. turned out i had a bad relay on my 5th cylinder.

WS62000

iTrader: (21)

Finally figured it out...It was the MAF Sensor

Xtnct00WS6

iTrader: (8)

I've had that exact same problem and it was part of a shitty tune. I had them put it back to the stock tune and start over. That fixed it and haven't had a problem since.

LS1LUNATIC

iTrader: (3)

What was wrong with it? My car has always thrown a code for a MAF malfunction and it a rough/lumpy idle w/ a stock cam. I too can feel a slight hesitation when accelerating, do I need a new MAF?

WS62000

iTrader: (21)

Not sure what was exactly wrong with it, but those are the same symptoms I had with my car. I have a 224/228 cam on 112lsa, so the idle is rough, but the hesitation was horrible at around 2000-2500 rpms, now, with the new MAF sensor, that is gone.

BLWN1

iTrader: (6)

will a MAF nor just die, but cause it to run rough? I replaced the 02 on bank 1, I hope that is the Dr side....

00454sscamaro

i heard of maf sensor cleaner, if its just dirty little coil looking things inside ( black and not silver) then id try that before buying a new maf. i bought a new maf, my acceleration increased alot and hesitation went away. but after looking at my stocker it was just dirty and would of probly been the same performance wise if i descreened it as the aftermarket one i bought. later my crank position sensor went bad and my car just kept running worse and worse, and i got a code for left bank lean after checking for spark and seeing i had none i asked a dealership they said crank ps and sure enough fixed it,easy to get to and replace to.. could be any number of things with these computer controlled everything cars but getting the code read if there is one usually a good start or dead giveaway.