I just purchased my second camaro.. a 95' z28 with the following mods done 25K ago... Bored,Cam,MSD Ignition,4lb Powerdyne supercharger,aluminum intake,Stock Aluminum heads,clutch,drives shaft,exc... The car likes to start sometimes and not others. I don't know if the injectors are stock or upgraded. If I put the key in and crank it over before the injectors are done spraying then the car won't start.. if I wait it will sometimes start but sometimes not... if it doesn't all i have to do is wait until the injectors are done spraying for the second time and it will start... Also when I am driving the car and I am hard on the gas it bogs out and backfires loud sometimes.. Doesn't really do it as bad at high RPM's but still does... Could this be a fuel pump since it won't start until after the injectors are done spraying or is it maybe the distributer plugs and wires that aren't igniting all the cylinders???? All I know is it is VERY annoying.. Oh yeah if i drive the car really good without getting on it at all it does not bog out or backfire??? only under acceleration... I appreciate any info. and sorry for the long post..:-)

 

Well, the injectors only spray whenever the piston is on the intake stroke, not before you start cranking it. It could possibly be the fuel pump, since it builds pressure when you turn the key on. Get a fuel pressure guage and check it out at idle, and while driving it. If I recall correctly, it should be around 36 lbs at idle, and 42 lbs or so at WOT.

I wouldn't rule out your ignition either. Coil/plugs/wires/opti could all very well cause the same probs you're describing.

With an engine with a lot of mods like that, it could very well be a number of things. Is it throwing an SES light?

 

It is not throwing any codes at all or atleast the light isn't coming on.. When I was saying injectors I meant fuel pump... How do I go about changing the distributer cap since it is in the lower front of the engine? any tricks to making this change easier.. what do I all need to take off to get to it.. thanks,

 

This is your first LT1 isn't it?

You'll come to know and hate the opti as time goes on. Here's a write up that I plan to follow when I eventually replace mine. Right now mine is getting a nice oil bath from an unidentifiable leak.

Optispark Install Page

 

yeah it is my first lt1.. also mine is a 95 so do I have that opti **** I thought I just had a distributer.. I'm very confused.. thanks,

 

Yep, you have an opti alright, along with every other LT1 owner. 95 was the first year of the vented opti, which is supposed to be less sensitive to moisture, unlike the previous years. Your opti is your distributor, it just doesn't work like traditional distributors. Do a search, and I'm sure you'll come up with more than you want to know about GM's little brain fart called the Optispark.

 

Oh man, hahaha, I'm sorry.. Goodluck and be patient.