7.4L vortec hard start

[dkh_524]

this has been going for way to long and getting kinda tired of it. i have been told it is always the fuel pressure regulator but i replaced that and it still does a hard start. it only does a hard start when i have been driving it and let it set for over 10 min.

a friend of mine that is going to school to be a gm tech and i replaced the fuel pressure reg last year. after we did and realized that it didnt fix the issue he did some pressure test and started to think that it is the fuel injectors. i probably should replace the injectors any ways because they have 190,000+ on them. but before i go and dump over a grand for them i would rather be sure that is the issue.

i think i need a new pump also because some times it does a big bang sound ha. and my fuel gauge flickers but after reading some info on here i think its the cluster witch really sucks.

could it be the oil pressure regulator as well that is causing the problem that flickers to so not sure.

any thoughts about what else it could be? any information would helpful thanks

 

[EmersonHart13]

I remember reading a post on FSC about someone that was having issues and replaced their Coolant Temp Sensor, seemed strange to me but worth looking at. I think you are hitting all the other things that come to mind.

 

[webxfx]

I remember reading a post on FSC about someone that was having issues and replaced their Coolant Temp Sensor, seemed strange to me but worth looking at. I think you are hitting all the other things that come to mind.

You might be on to something - cause mine doesn't work.

 

[dirtyhick42]

It is more than likely your injectors bubba. They are prone to going bad on 7.4 vortecs and leaking down causing a hard start after sitting for more than a few minutes. Good luck in fixing them on a big ass truck, I never replaced mine on my ccsb because I didn't feel like sitting in the hood the whole time being on 37s.

 

[454ss]

ive been all through this with the same problem and replaced a crap load of stuff. its in my post in the vortec section, havent tried a temp sensor but my gauge always works.

 

[dkh_524]

i have been under my hood a lot it seems like kinda used to it just sucks knowing how much all 8 coast to replace.

i didnt see the vortec section in your post. you have a link?

 

[454ss]

in the 96+ vortec sub forum, long cranking time/hard start

 

[outalne94z71]

ive been all through this with the same problem and replaced a crap load of stuff. its in my post in the vortec section, havent tried a temp sensor but my gauge always works.

the gauge sensor is not the one to replace, the ecm one in the intake is the one to replace, if it tells the ecm that the motor is cold when it is not it will dump fuel and flood it

 

[454ss]

outalne94z71, is that the sensor in front of lower intake under the thermostat ? (on a vortec 454)

 

[outalne94z71]

outalne94z71, is that the sensor in front of lower intake under the thermostat ? (on a vortec 454)

sounds right, there should be one for the ecm up there and the one for the gauge is in the driverside head, passenger side head sometimes gets a sensor to operate a electric fan