Ok so when I go to first start my truck in the morning or after its been sitting for a while. Right after the engine turns over this loud high pitched screeching noise comes from the engine bay I believe I havent been able to pin point exactly where but i think the engine bay.

I thought it was the fan scratching against something but its not its always right after the engine turns over or while its ending. I really need help I have no ideas what this would be. I was thinking lifters, the cam synchro problem that plagues the 3.0 I checked Tranny level and oil all fluid looks good.

Im also throwing a CEL as well I just kept on resetting the engine its the dreaded P0174 lean in bank 2 have not done anything for this but it did come on after I got my exhaust done after the last CAT.

The code has been on for a while and I believe that this noise started after the code has been up for a while.



PLEASE HELP ME!!!! its a 2005 3.0 auto 2wd 31,000 miles+

 

First check the belt tensioner . Put a wrench on the bolt and move the tensioner as if you are taking the belt off . Do this a few times to make sure it is not sticking .
Pick up a cheap mechanics stethoscope . Probe the tensioner and idler pulleys by placeing the probe on the mounting bolts with the engine running .
If the pulley bearings aren't it , remove the belt , start the truck and if the noise is gone replace the belt with a Gaterback.

 

You also might have dirt or something in your starter keeping the bendix gear from retracting properly after starting.

 

My 2000 3.0L did the same thing every other cold start, as did my sister's 2002 3.8L mustang and my friend's '98 3.8L mustang.

 

Its the starter if it just makes one loud skwwwek, but if it keeps screeching its the belts.

 

mine does the same thing but it only when its moist out or if it rainned the night before then it usually stops. i talked to the tech over at ford they said its nothing to worry about its normal when you get some moisture on the belt.

 

My brothers 05 3.0L does the exact same thing. I know its not the belt. The sound is just like you described, it seems like it is the starter because it is lower down in the engine bay.

 

Ok so I got the noise figured out Im about 95% sure thanks from alon @ modbargains and reading through several other threads, The starter it is from mudding and dust from AZ.

Now about the check engine its not the MAF it might be vaccum but what exactly am I looking for and how exactly do I go about checking for vacuum leaks