brycebba
I'm Awesome
- Joined
- Mar 16, 2014
- Messages
- 439
- Reaction score
- 19
My truck is a 96 k3500 with the vortec 454. I have a beast of a hard start issue and it is driving me freakin nuts!!!!!! I have done so much and nothing has helped, in fact, the hard start issue seems to be getting worse. It starts fine cold and if it is hot and I start the truck within little bit of shutting it off. Only when it has warmed up and sat for a while or its really hot outside and it hasnt run for a while does it do the hard start which it will crank for probably 10 seconds before starting. It didnt have an issue as far as I recall when I bought it in February but it has started and been getting worse since then. Also, being in utah the temperature has gone from about 40 degrees or so at that time to almost mid 90's daily now...not sure if that has anything to do with it because it may have cooled it down much quicker then and wasnt as noticeable? Ok, I will start with the few mods I have.
1. Magnaflow XL muffler
2. Superchips Flashpaq on Performance tune
Things I have done and it still persists
1. New 24lb injectors (tried two sets and no change)
2. New FPR stock 3 bar (tried twice just to make sure they werent defective)
3. New OEM fuel rail
4. New Coil
5. New plugs and wires
6. New cap and rotor
7. New fuel filter
8. New delphi fuel pump
9. New Ignition control module
10. New coolant temperature sensor
11. New PCV valve
12. heavily sanded ground for fuel pump so its getting a clean connection
13. Put soapy water over all fuel connections and looked for bubbles but have found none
14. cleaned EGR valve and it moved freely before but is extra smooth now.
15. Checked for codes and there are none
16. The timing reads about 26.5 at idle to 30+ when I rev it up
17. The data logging on my flashpaq seems to show that the 02 sensors pre and post cat are operating at the correct voltage
18. Cursed the truck and made my neighbors blush from my boisterous profanity
19. when doing the fuel mods the 4 times I took the plenum off I replaced the intake gaskets twice.
20. Checked the wiring going to the ignition control module because I hear it can get chafed and short but I didnt see any problems.
**When I took the plenum each time off a thing to note is each time I took the EGR valve and the black box with a vacuum line going to it off (sorry, not sure what that thing is called)
I have heard that plugged cats can cause some issues but I dont know if it sitting for a while would make it hard start compared to cool engine or quick restart not causing an issue.
So after all of this I have checked and rechecked fuel pressure after every change regarding fuel parts and it is now pressurizing better while running at 49 psi. I realized that my gauge sucks though because I cant screw it all the way down or it wont read. I have to back it off a few turns which may cause a minor leak so the psi may be higher but Im not sure and dont have access to another one. It is also possible that when I see it dropping pressure after I shut it off it is the gauge leaking down some. I can generally see it drop down to about 25 psi within 20 mins and stick there. I had a completely smooth idle after I did 1-9 in the list but then it started to get a little rougher more and more as the hard start issue has been getting worse. I am losing my mind and getting pretty frustrated with my new to me truck. All of those parts have definitely helped other running conditions, dont get me wrong but they just havent fixed this. My truck only has 65k miles so part of my reasoning behind replacing all that stuff and being ok with it is the fact that its a 96 and has that little of miles so I know it has spent some serious time sitting around.
1. Magnaflow XL muffler
2. Superchips Flashpaq on Performance tune
Things I have done and it still persists
1. New 24lb injectors (tried two sets and no change)
2. New FPR stock 3 bar (tried twice just to make sure they werent defective)
3. New OEM fuel rail
4. New Coil
5. New plugs and wires
6. New cap and rotor
7. New fuel filter
8. New delphi fuel pump
9. New Ignition control module
10. New coolant temperature sensor
11. New PCV valve
12. heavily sanded ground for fuel pump so its getting a clean connection
13. Put soapy water over all fuel connections and looked for bubbles but have found none
14. cleaned EGR valve and it moved freely before but is extra smooth now.
15. Checked for codes and there are none
16. The timing reads about 26.5 at idle to 30+ when I rev it up
17. The data logging on my flashpaq seems to show that the 02 sensors pre and post cat are operating at the correct voltage
18. Cursed the truck and made my neighbors blush from my boisterous profanity
19. when doing the fuel mods the 4 times I took the plenum off I replaced the intake gaskets twice.
20. Checked the wiring going to the ignition control module because I hear it can get chafed and short but I didnt see any problems.
**When I took the plenum each time off a thing to note is each time I took the EGR valve and the black box with a vacuum line going to it off (sorry, not sure what that thing is called)
I have heard that plugged cats can cause some issues but I dont know if it sitting for a while would make it hard start compared to cool engine or quick restart not causing an issue.
So after all of this I have checked and rechecked fuel pressure after every change regarding fuel parts and it is now pressurizing better while running at 49 psi. I realized that my gauge sucks though because I cant screw it all the way down or it wont read. I have to back it off a few turns which may cause a minor leak so the psi may be higher but Im not sure and dont have access to another one. It is also possible that when I see it dropping pressure after I shut it off it is the gauge leaking down some. I can generally see it drop down to about 25 psi within 20 mins and stick there. I had a completely smooth idle after I did 1-9 in the list but then it started to get a little rougher more and more as the hard start issue has been getting worse. I am losing my mind and getting pretty frustrated with my new to me truck. All of those parts have definitely helped other running conditions, dont get me wrong but they just havent fixed this. My truck only has 65k miles so part of my reasoning behind replacing all that stuff and being ok with it is the fact that its a 96 and has that little of miles so I know it has spent some serious time sitting around.
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