Lean codes bank 1 and 2

[DontBeJeff]

Don't be afraid to test and re-test. I have those two codes, and all smoke tests came back without a leak, and for a while so did the fuel pressure test. After a while, something will start to show. Don't just shotgun parts - I have learned that while I did replace some hoses that where definitely worn, none of them fixed my issue, and some parts that seemed good I replaced anyway and still no luck. In the end, it was the fuel pump that was going bad, as doing test over test I noticed that it kept getting worse, and because I don't want to do more work then I should, got a mechanic to verify that it was indeed going bad. Have that as a weekend project to replace it here in a few weeks, so hopefully that fixes my problem!

 

[blue oval guy]

Thanks for feedback, yes i was going to start with replacing some vacuum hoses, namely PCV elbows and hoses on both sides. What was the test for the fuel pump, just a gauge reading at the fuel rail while at idle? Thanks.

 

[Big Brian]

Just spray a little carb cleaner around the areas where you suspect a vacuum leak. If you have one the engine will speed up slightly when you hit it.

When I was doing this for a living there was no such thing as a smoke machine. We would always find them with carb cleaner.

But we did not have computer controlled engines back then either.

But if you have a decent leak it will show up with carb cleaner

Not that the smoke machine isn't a good idea, I just don't think its needed most of the time

 

[DontBeJeff]

As for the fuel pressure, on the passanger side bank's fuel rail, there is a schrader valve to put a fuel pressure gauge on. Look up the fuel pressure for the engine you have. I have a 5.4, so getting closer to 30psi and lower is starting to show that it was going bad for me. Also, it didn't hold pressure after turning off the engine. Not a big deal for a lean code, but it is also a sign that the fuel pump is needing replacing in the long run as it should hold whatever pressure it was at when it was turned off.