Running rich

[Parentnoia]

No other ideas?

 

[bluex]

Alright. Big update. Still running rich, but we've narrowed it done further.

Got the codes tonight.

• P0172 Rich Bank 1
• P0175 Rich Bank 2
• P0300 Misfire

Then we did some more investigating. We did a fuel pressure test. It sits at just under 60 running, which he says is fine. When we shut her off, it slowly drops to 20. "Well, it might be your fuel pump. But let's check on that misfire." We look on the scanner at the individual cylinders. All cylinders have a misfire history, but cylinders 5 and 7 actively. We stopped at the conclusion of a possible crack in the spider.

How long does it take the pressure to drop off? 10-20 seconds or 1-2 mins?

The codes are telling you that both sides of the engine are rich. Cylinders 5 and 7 are on the same side so its not just those two causing the rich condition. With the pressure dropping off it could be the fuel pressure regulator (fpr) inside the intake on the spider assembly itself. They are bad about leaking also and that would add unmetered fuel in your intake causing the overall rich condition on both banks. You can replace just the fpr but if you are in there I would just go ahead and throw in the the updated MPI assembly and go from there. New plugs (I like and have had good luck with NGK's in mine) and GOOD quality cap/rotor/wires while its apart are also a good idea.

 

[Parentnoia]

Well, all of my offline input, is coming from my uncle, who has 30+ years of working on cars, so take that as you may. As for the fuel pressure, it runs at just under 60, around 58. As soon as the key is turned to OFF, it jumps to 70 then straight to 40 in less than a second. And from there it drops to 20 within a few seconds. And as for replacing everything while it's apart, we are scraping the char off of the barrel at this point to make it around town, so it'll be a while before we can even get any remedy.

 

[Parentnoia]

Asked my grandfather a "This is what I would check, am I right question" about if it could be the spark plugs in anyway not sparking and he says it's very possible, so tomorrow afternoon we're gonna pull them to check them, starting with cylinders 5 and 7 to see.

 

[Parentnoia]

Nothing?

 

[Parentnoia]

Alright, since the problem is still persisting, I figured I'd revive this thread but take the time to state the symptoms chronologically.

1. Started with the day we bought the truck in May 2012. It's been hard to start. I have to let it crank for 10-15 seconds before it starts up, but some occasions (mostly cold mornings) it'll start right up. The previous owner said the problem popped up in the last few days after an oil change.
2. After a few weeks of drive it around, you could no longer feel the A/C condenser kick on when the button was pressed on the dash.
   Around that same time, we started to notice the smell of gas in the truck when the windows were down, but we just attributed that having just filled up.
3. Another few days later, we noticed that the smell is stronger under the hood and at the exhaust. When we noticed it under the hood, we were getting the oil changed and one of the other mechanics that was working with my uncle said it smelt like a EGR leak. When my uncle got home that night, I asked him about it and he said yeah, it could be, but not to worry about it. And he also said that the hard start issue could be the fuel pump (since you can hear a distinct whining from the rear of the truck which my uncle says is the fuel pump) or it could be the fuel filter.
4. So fast forward the October 7, 2012 when I decide to change my oil and while I'm under there, I decide to replace the fuel filter, but that didnt fix the problem.
5. Fast forward to Thanksgiving 2012 when I talk my uncle into hooking his scan tool up to the truck. That results in the codes:
   • P0172 Rich Bank 1
   • P0175 Rich Bank 2
   • P0300 Misfire
6. A week or so later, we run a pressure test that results in an idle pressure of about 60 PSI which spikes to 70 then down to 40 PSI (as one motion) immediately after turning off the engine then down to 20 in a matter of a couple seconds.

Now here I sit, with no improvement, wondering if there's something I still have not changed, like spark plugs, distributor, etc.

 

[Dubya]

if an injector is leaking fuel it creates the truck running rich sounds like unburned gas making it into the exhaust creating a smell of gas from the exhaust.

 

[Parentnoia]

Well, I intend to upgrade the spider in the next few months, but will that remedy the hard start?

 

[DGA1]

Hard starts could be from too much gas, so you are kind of SOL if the poppets are fouled, stuck open, and leaking, or even cracked. You could open the throttle body plate all the way and take a look inside with a flash light and look for any pooled fuel. Do this after cycling the key off and on a few times, not running the engine, but only running the fuel pump. An increase in gas smell after this, especially from the throttle body will be almost a sure fire way to tell there is something leaking in there.

 

[Parentnoia]

Hard starts could be from too much gas, so you are kind of SOL if the poppets are fouled, stuck open, and leaking, or even cracked. You could open the throttle body plate all the way and take a look inside with a flash light and look for any pooled fuel. Do this after cycling the key off and on a few times, not running the engine, but only running the fuel pump. An increase in gas smell after this, especially from the throttle body will be almost a sure fire way to tell there is something leaking in there.

So I should just go ahead and upgrade the injector assembly and come back if the problem persists. Gotcha.