Ictinik

Hey guys, I will start with the car

it is a '95 Camaro z28 6 speed.
MODS
Moates APU1 setup
Ported and polished "built" heads (stage 2) I have close to $1800 in these heads
long tube header Magnaflow muffler, and "muffler shop special" piping
4.11 gears
CRT elbow and K&N cold air intake
and a few other mild bolt ons.
stock bottom end
and a lunati 60122 cam waiting on me to finish the bottom end
replaced parts
Opti Spark (2 times just incase)
cap, rotor, wires, plugs
Ignition control module
intake gaskets and all vacuum hoses(incase their was a vacuum leak)
a few Injectors just incase they were bad
and I am sure there are a few thing I am forgetting
the problem I am having
The car just runs like crap... I should have a 12 second car(or close to it) and I have like a 15 second car.

My left side O2 sensor bounces from 100mv to 900mv while the right is fairly steady at 900mv (under acceleration)

My AFM seems to be a bit jumpy

and I stay in closed loop almost all the time

the car feels like it is missing, but I have been through the ignition system MANY times looking for it

every now and then the car will just start running right.... I know this because of the lack of traction in 3rd gear..but most the time I can not even slip the tires in 1st...

I was a service manager at a large auto shop, so I am pretty knowledgeable when it come to car, but this one has thrown me for a loop...


I will up load the last data log
*note on data log*
the 1st 1/2 is almost useless, I was just driving and waiting on red lights


Please ask questions, I really need help...LOL.

Ictinik

forgot the datalog

babbage1109

iTrader: (11)

So youve replaced everything but the o2 sensor that's acting weird? Have you checked grounds

Ictinik

I have not checked grounds.. I was planing on Buying a new battery and replacing the cables Wenseday. and while I was at it running a few extra grounds to make sure

Would a 02 keep the car in closed loop mode?

jaycenk

iTrader: (1)

ok closed loop is normal up to temp everything is working and open loop is waiting for O2's to heat up as well as the engine temp. With that said what headers are they? an exhaust leak will cause that.

Ictinik

I have been smelling exaghst, I will replace the header gaskets wenseday aswell...

think I should go ahead and replace the O2 sensors aswell?

I am not made of $$$ but I want my toy to be fun to drive again hehehe

Ictinik

UPDATE

Ok I had some free time today so I ran some new grounds and cleaned up all th connections I could get to easily. It seems to to be a bit better, but that could just be the cooler weather we are having.

In my first post I stated that the car would not get out of closed loop...I was having a brain fart, and it took someone pointing out that closed loop was were it was supposed to run

I could not data log for time issues so I will have to do that later.....

The car still feels like it has a miss.... and after some searching I think this is a common issue with the Lt1s but I have yet to find anywhere that states the fix...

Another Question

The O2 sensor...
a) they loose accuracy over time
b) they are good till they stop working

I have heard both ways and not sure what to beleive on this one

SO the question is, while I am under the car working on the header gaskets should I replace them? they are not showing any codes and in the logs they are fluctuating...will it be worth the $120 to replace them?

(dang real toy car are expensive..I might have to go back to the rc world..LOL)

94FBIRD

iTrader: (5)

My car acted EXACTLY the same when I had a broken valve spring. I also thought it was ignition and the O2 sensor acting weird confused me also. My pull your valve covers and check out the valvetrain. Even new springs can be defective.

Ictinik

going to be a busy weekend, lol.... I need to change the gaskets anyway, might as well pull the intake and fix that leak as well....

I hope this is not the case, I bet I could not get just one spring, lol...

This car is costing me a lot!!!! I could have bought a high milage LS6 car for what I have put in this already hahaha

Ictinik

from fear of a broken spring I went for another run...
I was completely shocked when I left the red light down the road.. I almost lost control The power was back more than ever!!!!.. It pulled hard and sounded great for about 1 mile then went back to the way it was before...dang I wish I had the laptop hooked up to see what changed...

So I am assuming that with the regain of power, and the subsequent loss of power after a mile can be attributed to the car switching into closed loop mode..and the exhaust leak(or bad O2) are the most likely culprits.

can't wait till I fix them and I get to terrorize the lovely town of Famerville Louisiana

Ictinik

I am not sure what fixed the problem, I think the 2 things that made the most difference was the new battery and the new ICM. the later being the best improvement, after data logging a few runs I noticed that my timing was stay around 40 degrees advanced.. all the time, I took the ICM as a guess and had it tested and it showed bad, so I bought a new battery and installed the new ICM and it runs great now. now to install the cam and work a bit on the tune

djjab57

iTrader: (17)

Maybe a loose rocker ? Bounced back on then back off ?! Just guessing

quik95lt1

iTrader: (7)

sounds like you got it solved.......however FYI the car should not be in closed loop mode while at WOT........

robsquikz28

iTrader: (246)

atleast you finally solved the issue...