Car wont start up

i have a 1998 chevy blazer v6 about 127000 miles on it.when i go and start up car the car starts right up.if i turn car off it won’t start back up so i give it a little gas it starts right back up.there is no check engine light

If this happens when starting the engine cold and then you immediately shut the engine off, this can cause a flooded condition. Then when you give it a little gas you slightly open the throttle plate which allows more air into the engine and it starts.

This sometimes happens to me when I start cold vehicles to move them in/out of the shop and then shut them off. I have to step on the gas to get them to restart because the engine is flooded.

Tester

it still does it when i drive it for 30mins

Then the problem might be with Idle Air Control valve.

https://www.rockauto.com/catalog/moreinfo.php?pk=1006115&cc=1029619

When you go to start the engine , the IAC valve allows a small amount of air past the closed throttle plate on the throttle body. If the IAC valve fails to do this no air enters the engine and the engine doesn’t start. Then when you step on the gas, you open the throttle plate which allows air into the engine and the engine starts.

Tester

ok thanks for your help and ill take a look into that

Dirty throttle bore. My Chevy did that for a long time. It would immediately die on hot starts unless I blipped the throttle. Cleaned throttle bore behind butterfly. Fixed it.

Mechanics call this problem “hot soak” I think. There are several possible causes, as mentioned above. From the symptom is sounds like it is running too rich on warm starts. The ECM is supposed to correct for that by using the coolant temp sensor. So one possibility is there’s something wrong there. You might google that term “hot soak” along with your car make/model and see if anything turns up out there in cyberspace. Maybe somebody else has had this problem. Best of luck.

I would guess leaking fuel pressure regulator.