Technical Tips > Post 84

hard starting....

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2 short:
no it does not come up with any codes.
must say though if i touch the gas pedal when cranking it does start easier.
i dont think this is a good practice because i believe this may cause flooding if it doesn't fire?
i think i will go away and check that cold start sensor.
thanks

White88:
Yes this right to an extent, opening the throttle slightly will cause flooding, but opening it all the way will help clear a flooded engine.

Extract from Corvette Fuel Injection by Charles Probst. 1982 - 2001
Clear Flood:
Corvette clear flood mode either provides a lean A/F mixture of 20:1
or completely cuts off the fuel flow so that the overrich mixture is swept out.To use Clear Flood when engine does not start, turn the ignition while holding down the accelerator. Applying Clear Flood will usually sweep out a flooded engine with air. Of course no other sensors affect the computer control of the injectors during this mode .When the engine catches, release the accelerator. When you ease off on the accelerator, the computer switches out of Clear Flood.

Yes I think you could be on to something there, the cold start sensor is temperture sensitive it's like the old fashon choke, colder it is more fuel it dumps, hotter the motor is less fuel, sounds like it's not working that well if you have more luck stating with a slightly depressed pedal.
Please post when you find the culprit.

Good luck Cheers...

White88:
Iv'e had another thought on the subject guys.
My car has just started to do the same thing, start cold great, start hot even after leaving for several hours no good. I placed my fuel pressure gauge on , with the vaccum disconnected the fuel pressure is 44 psi, which is normal , after waiting half an hour it dropped to 20 psi ( not normal). Now I have a new fuel pump and new regulator already fitted about 4 months ago, so I suspect the leakage is coming from my injectors, which is making it hard to start because 1) there is no fuel in the rails 2) all the fuel is inside the motor (flooded). Now knowing that the cold start injector is heat sensitive the cold start injector should not be working anyway because my motor is still too warm for it to work. So if my car starts every time first up when it's stone cold  that means the cold start injector is working correctly !. If my fuel pressure didn't drop then maybe cold start sensor could've been the problem. I suspect opening the throttle slightly as 2 short was describing will help clear the flooded engine enough to help start.
I don't know if this helps or not but might be worth a look, just my 2 cents.


P.S.  2 short if want more info on checking for leaks in your fuel system -regulator, fuel pump check valve / or hole in pressure feed line and injectors just let me know, if you want a lend of my fuel pressure gauge just let me know as well as I don't live that far from you.

:<>

2 short:
thanks for that info.
i have a fuel pressure gauge permanently fitted to the rail so i will check that out.
also noticed on saturday (very warm day) first start up for about a week i took a while to fire.

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