4u 2 nv

iTrader: (29)

have a 2002 Z28. mods are QTP LT, Off road y pipe, corsa catback. RWTD tune diablo, ASP Pulley, Lid, Descreened MAF, MSD wires and NGK tr55.

Does not do it all the time. Under light loads like pulling away from light or stop sign, light acceleration in traffic. car likes to jerk and buck. if i happen to catch it at a stop sign. idle drops to around 400-500 RPM but wont die completely. and it then sets a random misfire code. Hooked a fuel pressure gauge up to the rail and even when it bucks/jerks it still holds 60PSI fuel pressure. it has OEM fuel filter with 41K miles on it. just got a new one and im gonna put it on. when it starts to jerk/buck if i go wide open it clears up. any help? thanks

ArcticZ28

iTrader: (14)

It's in the tune. Check your VE and STFT tables at the lower RPM's you are talking about.

joe_kool315

sounds like what mine did when I had a #2 fouled plug. find out which cylinder your getting the misfires in and I bet that plugs fouled... or just change them all . if the misfire code is in multiple cylinders you "may" have more than one plug fouling or it could be a tune issue but with basic bolt-on's you'd be hard pressed to get a tune to do that unless you have a super aggressive one.

4u 2 nv

iTrader: (29)

i kinda think its plug also. that tune has been in the car for 15k miles and this has only started in the last 4k or so. kinda wondering now what i did to possible foul out a plug?

ArcticZ28

iTrader: (14)

Ahhh gotcha, I thought you had just tuned it. Def check the plugs/wires then.

joe_kool315

not "always" something you did or didn't do to foul a plug. AF mix might be rich and burning a little oil through the notorious PVC oil consumption the LS1's have could be a number of things ... I foul the 1,2 and sometime 3 plugs ever so often but I also go through a quart or better oil every 3K miles and smoke (black) under heavy full throttle acceleration. AND the car runs pig rich at WOT also but I have a stock tune with engine back exhaust (headders ORY pipe and corsa CB) with the TSP lid and power shot filter smooth bellows up front. I guess "most of the oil gets sucked down the first set of runners going to the #1 & 2 cylinders and that's why they foul. nothing I do or didn't do (except get a proper tune )

4u 2 nv

iTrader: (29)

all right just bought new tr55's adn we will see what happens......thanks for the help guys.

redline2k

iTrader: (9)

Check the wires also remember ed's problems.

4u 2 nv

iTrader: (29)

yeah ive checked all but the passenger rear and none are touching. ill put it in the air at work and check it.....so how have you been glenn?

kapedogg

iTrader: (5)

I had a similar problem. Turned out a handful of wires were melted on the passenger side header including two that ran to the crank sensor. might want to check that out.

rd_ls1_z

Mine did the same thing as yours 4u 2 nv, and it's in the shop now. In my case, I have lean codes on cylinders 2 and 6. along with random misfires, so they're checking my injectors on those cylinders.