Hard Cold Starts

[Yamahaulin]

When starting my car after it sits overnight it cranks forever before it starts up. Kinda like there is no fuel in the lines and must pressurize the line again. Once started or been running for a while i can restart instantly even if it has sit for an hour, but overnight it's drained again. Why do these cars not prime the fuel pump when the key is in the on position? How do i fix this problem. I have a walbro 255 intank pump.

 

[nothingfiction]

Sometimes i have the same problem too.
i don't know if it is a fuel problem. Not sure it's not tho.

For me on a cold start it cranks and usually turns over. But sometimes it stalls then dies. But its more rare for me. Only started about a month ago and has only happened about 3-7 times yet.

 

[boostedjay32]

Just tap the gas pedal. Thats what i do haha =]

 

[crash89]

Check your guys coolant temp sensor.

 

[Yamahaulin]

My coolant temp sensor is good. I have a fuel pressure gauge and it reads 0 after sitting overnight. So i would imagine all the fuel has leaked back into the tank and the lines are empty. Is there not some kind of check valve to prevent this from happening?

 

[awdwhip]

My coolant temp sensor is good. I have a fuel pressure gauge and it reads 0 after sitting overnight. So i would imagine all the fuel has leaked back into the tank and the lines are empty. Is there not some kind of check valve to prevent this from happening?

It's normal for your fp to go back down to 0 after letting the car sit over night.

There is no "check valve" anywhere in your fuel lines to keep them from draining back to the tank either ans as soon as you start cranking the car you should have full line pressure. By any chance is this on ethanol?

 

[Yamahaulin]

No ethanol just 93 octane shell. I guess i should rewire the pump to come on with the key that way there is pressure before i start cranking.

 

[dsmfa9nutter]

Your fuel pump spins when the cas spins. On a properly running car, it shouldn't take more than a crank or two to start. If you have fuel pressure right away, it could be your coolant temp sensor even if the cel doesn't come on. Double check the wires running to it too.

 

[nothingfiction]

When it first started happening to my car i figured it was electrical like it may be my alternator or my battery, a friend mentioned it may be the starter. But my problem started to go away when believing it may be one of those (mainly the batt) i started to turn my radio volume all the way down to -0- before turning the car off. And it hasn't happened again since.

 

[DSM1G90]

Isn't there a check valve in the FP itself, esp stock FP's ?

To check my FP is do that jumper test with that small connector, a jumper wire attached to that small connector (which is next to the timing grounding connector behind the battery), touch the battery positive post and squeeze the pressure build up in the fuel return line from the regulator on the rail.

I bet your ECU is beginning to cave in for I was experiencing the same hard start problem for it's not actuating the injectors (FP is okey and esp when I would shoot starter fluid in the Throttle bore and it would fire up immediately) - now it's out for some warranty work ...

 

[Yamahaulin]

Your fuel pump spins when the cas spins. On a properly running car, it shouldn't take more than a crank or two to start. If you have fuel pressure right away, it could be your coolant temp sensor even if the cel doesn't come on. Double check the wires running to it too.

Do you have a pic of which sensor to test?

 

[EagleTalonTim]

The sensor you need to test is the only coolant sensor which has 2 metal plugs sticking out of it located on your thermostat housing. One lead is vertical, the other is horizontal. It kind of looks like this ( -- | )
Be sure you check the wires going to it too. Mine looked connected, but the wire in side the insulation was actually broke completely.

 

[dsmfa9nutter]

Isn't there a check valve in the FP itself, esp stock FP's ?

Fuel pump turns off, fuel drains out of the lines, there's nothing there to keep the lines pressurized.

 

[Yamahaulin]

I don't have anything plugged into that dual connector coolant sensor onlyhave something to the single prong one. I have no loose plugs laying around. Where does this plug come from and what color are the wires. I found 2 cut wires one is red the other black coming from the harness. Could these be the wires that are supposed to hook to that sensor. Some help would be greatly appreciated.