I have a 96 Z28 that has been getting progressively worse at starting. At first it would turn over a few times before starting, but it now has gotten to the point where it will crank for 10+ seconds when cold. If it's warm and been sitting for a few minutes it'll crank for a couple seconds and run rough as **** and feel like it's about to stall any second. It usually takes a few more seconds to recover to a normal idle and then it's fine. It usually smells pretty strong like gas.

Other then that it runs great. There's some hesitation at WOT near the redline where it feels like its starving for gas, but its not a big deal.

Any ideas?

It's got about 130,000 miles on it.

Here's a video of it before it got worse:

http://www.youtube.com/watch?v=umx0JzoAjnw

 

have you had it scanned for trouble codes? scaning for codes may give us a better idea were to look. could be a fuel pump failing so check the fuel pressure. http://shbox.com/1/4th_gen_tech2.htm...essure_testing can also try this,,, at first start try cylcling the fuel pump a few times, by turning the key on and off, before trying to start it. whens the last time it had new plugs installed? bad plugs can make a big difference. how old are the 02 sensors? have the injectors ever been cleaned and tested? could also be the evap system failing. theres a sticky to tell you how to do that at the top of the lt1 section. https://camaroforums.com/forum/lt1-lt4-tech-9/testing-evap-system-51219/

 

Just to piggy back on what Craby said also check the air filter, fuel filter and also if the MAF screen is blocked. My Wife's Z was hard starting and when I checked the air fliter I found that the hose to the air box had gotten messed up and allowed air in behind the filter and there were leaves and crap stuck to the screen. Removing them made her car start normally.

Massey

 

Thanks a lot for the replies guys.

I was thinking something along the lines. I cleaned the filter which wasn't too dirty anyway, and the MAF sensor and screen with some MAF cleaner I had lying around a couple days ago. Think I'll probably check the fuel filter by checking the pressure today.

Yeah I bought I scan tool a couple weeks back. No codes show up.

I'll grab a fuel pressure tester today and try to test it today or tomorrow.

Thats pretty much the only way I get the car to start now.

Years. TBH the plugs that are easy to get at look fine so I haven't gotten around to changing them. I wouldn't be surprised if the optispark goes soon either though. The water pump ended up dying and I had leaks everywhere spraying coolant all over it for a while.

As old as the car I assume. Never looked at them as long as I've had it (a few years). Doubt the injectors were ever looked at either.

I'll look into this after I check my fuel pressure.

 

This leads me to think the fuel pump is about to die. I had to do the same thing to my old 01 Alero and then keep on the gas till the engine built up a little heat then it would idle. Checking fuel pressure at idle engine warm (like the book says to do) showed good pressure. After I replaced the pump the problem went away.

Massey

 

Yeah you're right.

Turning the key without starting the engine gives me about 5 PSI. With the engine running, I get about 35 PSI.

When I put +12 into the fuel prime connector it built up to about 15-20 PSI over about 10 seconds.

From what I can see online, this looks like its going to be the biggest pain.

 

It really is not that bad. I have seen and worked on cars worse for dropping a tank than the 4th gen Camaro. Having little to no fuel in the tank helps.

Massey

 

changing fuel pump is much easier if you do the hatch mod.