22% Lean on bank 2 HELP!

[Arissett]

So ive been running pretty lean to say the least. I misfire when stopped at lights or just stopped in general. I do have some acceleration loss of course. My computer also won’t throw a code although I know i’m running lean because of the live data on my scanner. I bought a smoke test machine and a fuel pressure test kit to diagnose. I’ve replaced my injectors and entire pump assembly along with wires and plugs. What kind of vacuum leak could cause 22% lean? 1999 5.0L Explorer.

 

[Turdle]

Maybe injector o ring leak. That surface needs to be cleaned well.
Possible bad " new" injector .

Can you pull bank 2 spark plugs, and lay them in order for a picture for us to look at? Spark plugs will tell if it's one cylinder causing the fuss

 

[Arissett]

Maybe injector o ring leak. That surface needs to be cleaned well.
Possible bad " new" injector .

Can you pull bank 2 spark plugs, and lay them in order for a picture for us to look at? Spark plugs will tell if it's one cylinder causing the fuss

Will be a little while before i can post a pic but will do !

 

[J_C]

I assume that it was doing this before you replaced anything? If not then did you reuse the fuel injector o-rings? It needs new o-rings if the injectors are removed or replaced.

Since you have the fuel pressure tester, might as well get that reading since it's so quick and easy to do. However you only mentioned bank 2, so does this mean bank 1 is doing better? If so, then I would expect that low fuel pressure isn't the primary problem as that should affect both banks.

If fuel pressure is good, I'd wonder about an intake manifold gasket leak. You stated you bought a smoke tester, so this might be a good use for it to check that.

 

[Arissett]

I assume that it was doing this before you replaced anything? If not then did you reuse the fuel injector o-rings? It needs new o-rings if the injectors are removed or replaced.

Since you have the fuel pressure tester, might as well get that reading since it's so quick and easy to do. However you only mentioned bank 2, so does this mean bank 1 is doing better? If so, then I would expect that low fuel pressure isn't the primary problem as that should affect both banks.

If fuel pressure is good, I'd wonder about an intake manifold gasket leak. You stated you bought a smoke tester, so this might be a good use for it to check that.

So yeah it was doing this before i replaced anything. When I did the injectors it came with new rings and everything. The misfires went away after for awhile with the new injectors but the lean percentage did not move even after the new ones were in. The misfiring recently came back in the way i described in the initial post. All of Bank 1 and short term bank 2 stay anywhere from -3 to 3. I also did replace my upper intake manifold gasket when i did my injectors. Obviously will test with my smoke machine when the weathers good but i don’t think it’s that.

 

[Arissett]

I assume that it was doing this before you replaced anything? If not then did you reuse the fuel injector o-rings? It needs new o-rings if the injectors are removed or replaced.

Since you have the fuel pressure tester, might as well get that reading since it's so quick and easy to do. However you only mentioned bank 2, so does this mean bank 1 is doing better? If so, then I would expect that low fuel pressure isn't the primary problem as that should affect both banks.

If fuel pressure is good, I'd wonder about an intake manifold gasket leak. You stated you bought a smoke tester, so this might be a good use for it to check that.

So i did my smoke test and it did not go as i thought it would. My IAC valve gasket is shot and i have a miscellaneous hole in my engine. A lot of smoke was just pouring out of this.

 

[J_C]

I can't see anything in the picture. IAC valve gasket, I think mine came with a silicone rubber gasket but places sell a paper alternative gasket or you could pretty easily cut one out of bulk gasket material.

The rest of the leaks, that's unfortunate depending on where they are. At least you were able to do the smoke test to see what you're dealing with.

 

[Turdle]

You are missing at least one lower intake manifold bolt. Pictured hole should have a shoulder bolt.

However, it's on bank 1. That's why I say at least one. I'm assuming one is mia on other side also.



Considering the title of this thread, it's lower intake gasket time. Get a tube of motorcraft grey silicone, and, a gasket set. It'll have iac gasket most likely.

I may have some bolts If you need em.

They could be broken off. We'll see I guess