C5 Hard to Start
Thread Starter
Racer
Joined: Apr 1999
Posts: 254
Likes: 0
From: Murfreesboro TN
C5 Hard to Start
I have a 99 coupe and just recently it has been very difficult to start after sitting for a little while. I need to crank it off and on for maybe about a minute before it fires up. Once started, all is fine. If I shut it down and then try to restart immediately, it fires right back up. It's seems to be only when it sits non-running for a few hours or days that it becomes hard to start.
I replaced the fuel filter and cleaned the throttle body, but still the same. Anyone else ever had this problem? Is it the fuel pump (although it run fine after starting, as I said)?
I don't beleive its the injectors or coils, since it seem to run fine once strated, but.....
Any advise out there.
I replaced the fuel filter and cleaned the throttle body, but still the same. Anyone else ever had this problem? Is it the fuel pump (although it run fine after starting, as I said)?
I don't beleive its the injectors or coils, since it seem to run fine once strated, but.....
Any advise out there.
Instructor
Joined: Aug 2005
Posts: 133
Likes: 0
From: OKC OK
Cold start circuit? Slightly leaky injector? I helped a friend diagnose a 3.2L Porsche DME car that had cold start problems due to a bad thermo sensor not completing the cold start circuit.
On my own car (911 SC), I had to clean a "cold start bypass" valve that opened to allow extra air to enter the system (controlled leak) in order to start. A different animal for sure, but at least it *may* give you an idea of what may be going wrong.
Also, not sure on Corvettes, but some Bosch injection systems required residual pressure to be held in the system...loss of pressure equaled longer crank times.
Just food for thought.
R.
Dustin
On my own car (911 SC), I had to clean a "cold start bypass" valve that opened to allow extra air to enter the system (controlled leak) in order to start. A different animal for sure, but at least it *may* give you an idea of what may be going wrong.
Also, not sure on Corvettes, but some Bosch injection systems required residual pressure to be held in the system...loss of pressure equaled longer crank times.
Just food for thought.
R.
Dustin
Thread Starter
Racer
Joined: Apr 1999
Posts: 254
Likes: 0
From: Murfreesboro TN
konish, thanks for the thoughts. I don't know whats going on. No DIC codes to indicat any problem. I just pulled the negative terminal on the battery to maybe "reset" things, maybe that will help.... 
Melting Slicks
Joined: Mar 2004
Posts: 3,365
Likes: 0
From: Farmers Branch TX
Cruise-In VI Veteran
St. Jude Donor '09
Does your car actually crank when you turn the key, because mine is doing something weird lately and I am curious if its the same thing, I have to put the clutch to the floor, and turn the key off/on about 20 times for it to start, but its very intermitent, every time i take it to the shop it wont do it for the techs.
Thanks,
--Chris
Thanks,
--Chris
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Thread Starter
Racer
Joined: Apr 1999
Posts: 254
Likes: 0
From: Murfreesboro TN
Chris,
Yes the car cranks. It just won't fire until it cranks over for about 30 seconds or more. That why I belive it a fuel line problem. Once fuels avaiable, varrooom, starts right up.
lv
Yes the car cranks. It just won't fire until it cranks over for about 30 seconds or more. That why I belive it a fuel line problem. Once fuels avaiable, varrooom, starts right up.
lv
Melting Slicks
Joined: Mar 2004
Posts: 3,365
Likes: 0
From: Farmers Branch TX
Cruise-In VI Veteran
St. Jude Donor '09
Ok thanks, I believe mine to be an electrical problem somewhere. I would think someone would be able to diagnose it quickly if it would do it more than once in a blue moon. I have taken it in 3 times for this problem, everytime I take it in, it wont do it, it sits in my garage overnight, and next morning, wont start.
--Chris
--Chris
Burning Brakes
Joined: Oct 2000
Posts: 832
Likes: 0
I'm having the exact same problem. I need to cycle the key to build fuel pressure before it will start. After a few cycles it will try to start and then after about 10 cycles, it will start. 
Did you fix your problem with the new check valve hose? I've got a 99 FRC
Did you fix your problem with the new check valve hose? I've got a 99 FRC
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
check the fuel pressue and residual pressure.if the car doesn't hold pressure after you turn it off,you found your cause.you just have to find the problem,be it a regulator,injector,check valve,etc
