Ls1Bait

Mine shook before the cam but much more after it

Revelation Z28

iTrader: (10)

its a normal LT1 thing.

when you get poly mounts itll go away but youll feel it in the car.

slohatch91

is your maf descreened? thats what mad mine do it i think. i have tryed everything else.

dhdenney

iTrader: (53)

You got that backwards.

BizZzatch350

iTrader: (33)

Tanner,

I'll try that this weekend, i bet it needs to be cleaned any way.


I have had this car for 7 years, most of which with a poly trans mount, it wouldnt cause the car to shake like it does at idle. I know what normal idle shake is like, barley noticable, this is very noticable.

FAD2BLK93

I think you have that backwards, the car reads from the 02s in closed loop, and has a set peramiter in open loop. My car runs a whole lot better in open loop, so I unplugged one of the 02 sensors. As for the coated headders the non heated 02s have a hard time heating up to 600 deg where they start to work that is why people do the heated conversion when they put them on.

Z48LT-1

FAD2BLK has it right. There's a very well written article at http://members.aol.com/InjuneerZZ/ScanMast.htm, which is primarily an explanation of what you can learn from the ScanMaster diagnostic gizmo. The pertinent discussion of open loop/closed loop is about halfway down the page, at INTRODUCTION - AIR/FUEL MANAGEMENT MEASUREMENTS:

Cheers -- Gary

carzman5678

Damn...see what no sleep does to ya.

Joshua Rosancrans

So my 1994 Firebird lt1 has an odd shake problem. It seems to be random. While driving it will shake once, twice, or maybe even a few times. After this it is fine for a little while. During some drive cycles, it may only do it once or not even at all. It kind of feels like if you shift in a car when you have a really hard shift kit in it, accept its random. Any ideas?

Project_Daily

I'd definitely scrutinize your O2 sensors if I were you. My car did exactly what you're describing when I had a bad 02 sensor; it would run perfectly when cold, but as soon as it went into open loop the AFR would drop to super lean when the pedal wasn't being pressed. It would shake and sputter sitting at stop lights like it was about to die but never would, and as soon as I started moving again it would be fine

BizZzatch350

iTrader: (33)

Just an update though 13 years later, it was an issue with the non heated oxygen sensors, switched to new heated oxygen sensors and the issue was solved.

SS RRR

iTrader: (2)

Thanks for the update!

BizZzatch350

iTrader: (33)

Some one bumped the thread, the world needs to know. Now I have that GTA, I have to look back at Thirdgen.org, and most the threads range from maybe 2001 to 2007 at the latest, so most links are dead or part numbers long discontinued.

Vicious95Z28

iTrader: (1)

My car idles much better in open loop these days. I've noticed this since I put it back on the road. As soon as our goes closed loop the sound changes completely. I've ran 112 leaded through it allot though and I'm thinking the O2's are pissed at me. Next on my agenda is a good Throttle body cleaning and new O2'S