engine issues

[MaineRanger]

Ok so I have two issues , they may be related or not at all. About this time lastyear I was getting a strange noise from under the hood, it sounded like a shop vac that had a piece of paper Stuck in the tube mixed with a fog horn, it only happens when its cold out at lower speeda and rpms, you have to rev it up a little to get it to go away, some times it happens w/ the ac on sometimes w/o, it always happens in slow moving stop and go traffic. I have tried tp get out and listen but never been successful because it stops when you are parked for more then ten secs. Any ideas ?
my other issue is an engine code of too lean, some times on bank one some times on both, this started happening ahout two weeks ago. Checked for vaccum leaks amd got nothing, I am thinking mabye a bad fuel filter or other fuel line items scince this started after filling up with some old gas and fixing a rotted out fuel filler neck. What do you guys think, am i right to think that if its not a vaccum leak?

 

[tbirdsps]

You've provided a couple of clues:

1. Sucking noise
2. Lean (intermittent)

Check very carefully the tubing from the air filter all the way to the throttle body. I'll be there's a loose clamp, bad gasket on the MAF sensor or a big crack in the tubing. Sucking air will make it run lean. I'm leaning towards a crack in the air intake tubing.

 

[MaineRanger]

you know what now that you mention it i do remeber that the last time i changed the filter i over tightend one of the bolts and cracked the mounting plate a little wich dug into the gasket. this is on the k and n fipk air intae of course. which would explain the noise but the crack is before the maf. I will check it out though and see if one of them goes away.

 

[Joe Olson]

my names Joe havehad several of these horn sounding noises in mainly older 4.0s found the only repair is to clean egr passeges and idle air control or replace. also therally clean throttle body. if you can grab the air inlet tube and it vibrates as this sound is there this is your fix.

 

[hondaxr650]

More than likely the IAC valve. Very common.

 

[MaineRanger]

ok so here is what i found so far nothing on the intake tube, maf or or air filter as to cracks or leaks. still have to try cleaning the maf and changing the fuel filter and try out some fuel system and injector cleaner and see if that makes the lean codes go away.

as for the humming i have replaced the punctured gasket with no success, but seeing as i have no egr on my truck i will deffinatley look into the IAC, from the sounds of it on other forums this is a pretty common issue and solution when done right. i will be doing that tomarrow and we will find out for sure.