Hesitation , hard to start after runnung

Engine Runs Rough, Stalls, Hesitates on Acceleration, Hard ...

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Ford Probe Engine Runs Rough, Stalls, Hesitates on Acceleration, Hard Starting, Poor Performance. This is a verified problem based on 9 reports. Learn more ...

Starting Problems - 1997 Ford Probe - RepairPal

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Dec 5, 2010 - Starting Problems on 1997 Ford Probe ... If the engine runs rough,stalls, hesitates on acceleration, is hard to start, or has generally poor ...

A new misfire/hesitation on accel. Problem.. - ProbeTalk.com Forums

forums.probetalk.com > Tech Section > 2nd Gen (93-97) V6 2.5L

My guess is you have an engine temp sensor not operating properly. The cold start is OK but there is something not telling the ecu when hot. There are multiple sensors and you may need specialist help to test them. There is a dedicated fuel management system on vortecs but I think that's on later models.

Throttle plate may need cleaned and check your plugs.

Here is the common cause of surges, cold stalls, stalls at stops, slow idle speed, erratic idle speed, rough idle and engine hesitation (and other problems), it is in most cases the idle speed control air-bypass valve and or throttle valve and upper intake, these area's get full of gunk and combustion residue over the miles and cause idle issues (stalls, low idle) like yours.

To correct this problem Buy a can of throttle valve cleaner (it is made by CRC) from the local auto parts store, NEVER USE CARB CLEANING SPRAY, IT DESTROYS THE ANTI-STICK TEFLON COATING, spray it into the air intake through the throttle body of the engine until you have used about half the can, you will need to hold the idle up while you do this, it will try to stall, after this shut the engine down and disconnect the Negative (-) battery cable for 5 minutes. The intake is now clean, if you continue to have the idle speed control problems you may need to seek the help of a professional.

Do you own a professional type scan tool that show's engine sensor data ?
048 Engine Hard to Start or No Start Scan Data for Starting Problems
003 Fuel System Tests Scan Data Tests

Seems like the coolant temperature sensor is giving the computer erroneous readings, and it is not adjusting the fuel mixture properly for cold engine operations. You should have the check engine light on, indicating this malfunction. The idle fluctuations are normal. The engine is trying to die, from the improper cold mixture, and the computer (ECM), recognizing low idle speed, is sending it back up. Another possibilty is that the butterfly on the throttle body is not closing completely, to allow richer mixture needed for cold starts.

Cold start injector could be bad, or you could have a small vacuum leak, like a cracked hose. A vacuum leak is most noticeable at idle, when engine cold.

I have a 1988 dodge ram charger with a 318 motor with throttle body. It runs really good when I start it up and drive it for about a half of an hour.
But after that when I step on the throttle a little bit, it hesitates. If I let off a little bit, it will go or if I really step on it, it will go also, but if I just hold it there, it really hesitates If I stop, the idle jumps up and down so much it causes itself to stall. It seems to only do this at low RPM's. If the RPM's are higher it's fine

Check the fuel pressure regulator. Pull off the vac line when you shut it off and make sure no fuel leaks out of the regulator.

check your Throttle Positioning sensor that should fix your rough idle the TPS controls the breather on the front of the engine its affixed to the right hand side of the throttle body just infront of the spyder on the V6 Vortec 4.3L Models