Start up

[96z28SideSwype]

I need help with start up my car starts up fine after it sits for a couple of hours but after like 5-30 mins it's a total bitch to start needs at least half to full throttle to start is that a sign of too advanced timing or not enough?


Silver 96 Z28 Silverback-DD
Green 96 Z28 Greenbean-Drag car

[popo8]

If im not mistaken part throttle shouldnt change anything on our fi cars. Full throttle will close the injectors... thats it.

[Camaro96]

I had something similar happen to me a few years ago with my 96 Camaro. I replaced the Opti and it was a fuel pump.

[zoomo]

popo is right on the throttle, and i would probably guess fuel pump too....you can always spray some starting fluid or brake clean and see if it will run off of that....

and of course there is a shrader valve on the injector rail you can hook a gauge to if you have access to one.....

[96z28SideSwype]

I'll check it here at work what should I look for would shbox have the pressure. I'm going to change the plugs tonight


Silver 96 Z28 Silverback-DD
Green 96 Z28 Greenbean-Drag car

[zoomo]

I believe its 35 key on engine off, and 40ish running....

Edit: just re read your original post.....why are you curious about timing? I noticed you had another post about tuning....has the timing been adjusted?
If the timing is too retarded, the engine will struggle to start and will rev sluggishly....if it is too advanced it will either kick back violently when cranking or act similar to a dead battery....like ruh.....ruh.....ruh..... Start

[Revolutions]

It could be a number of things a couple off the top of my head.
Bad IAT sensor or circuit, when bad or high circuit resistance the computer read -40°f.
Leaking injector will flood the motor and :30 isn't enough time for the fuel to evaporate.

If you have access to a scanner check the IAT and if you have a fuel pressure gauge
cycle the key and see how long it takes for the fuel pressure to bleed off.

[96z28SideSwype]

I know the timing has been messed with and I'll check all this when I can


Silver 96 Z28 Silverback-DD
Green 96 Z28 Greenbean-Drag car