5.7 vortec long crank

[m002922]

As dumb as this sounds, for a fuel pressure issue, check the fuel filter. I had a lot of the same symptoms, and my fuel filter was only like 10k miles, but it had collected a lot of stuff and was preventing good pressure.

 

[slow_c1500]

As dumb as this sounds, for a fuel pressure issue, check the fuel filter. I had a lot of the same symptoms, and my fuel filter was only like 10k miles, but it had collected a lot of stuff and was preventing good pressure.

I just thought about that, I replaced the fuel filter and added sea foam into my tank. I’ll drive it around for a bit to see if it fixes the hard start and my new code for a cylinder 7 misfire.

 

[slow_c1500]

So I am now getting a code for a cylinder 7 misfire. I pulled the spark plugs and plug #7 is wet with fuel and the rest aren’t. My first thoughts are that injector #7 is leaking? This would make sense, as this would cause low fuel pressure which is related to my hard start.

 

[Schurkey]

Clean or replace the plug, see if that cylinder comes back to life.

Maybe verify cap, and plug wire for #7.

 

[slow_c1500]

Clean or replace the plug, see if that cylinder comes back to life.

Maybe verify cap, and plug wire for #7.

I cleaned the plug and it fixed the misfire for a couple miles but the code is back. still has a hard start.

 

[slow_c1500]

After further investigation, it seems spark plugs 3, 6, 7, and 8 have fuel deposits on them, yet 7 is the only one throwing a misfire code. Thoughts? I am starting to think the spider or pressure regulator may have failed and is flooding the engine, or maybe the ICM which would explain the spark problems and hard start when warm.

 

[Schurkey]

I'd start with inspecting the cap and testing plug wires. Cheaper and easier.

 

[slow_c1500]

I'd start with inspecting the cap and testing plug wires. Cheaper and easier.

I swapped the plug wires around and the misfire remained on 7. What would the cap look like if it isn’t working?

 

[Schurkey]

Heavily corroded, contaminated inside, and/or carbon tracked. Vortec caps may misfire from one conductor to another as they cross each other within the insulating plastic of the cap.

What is the cranking compression pressure of #7 compared to a "good" cylinder?

 

[slow_c1500]

Heavily corroded, contaminated inside, and/or carbon tracked. Vortec caps may misfire from one conductor to another as they cross each other within the insulating plastic of the cap.

What is the cranking compression pressure of #7 compared to a "good" cylinder?

I don’t know the compression pressure. How do I measure that? Also could this problem be related to my hard start?