hello all...i have a fairly new to me 2000 4.2, it always starts right up in the morning or ive noticed if it sits for a while it will start right up....BUT..if i say just run to the gas station and go to start the truck back up it just cranks and cranks..BUT, if i put the gas pedal to the floor it will slowly and eventually lub lub lub and completly start and then idle really high for a minute or so

i took it to get scanned and got this
P0174-bank 2 combustion too lean
P0125-insufficient coolant temp for closed loop
P0172-system too rich(bank1)

they recommended i look for a vacuum leak, which makes sense becuase when im driving i can hear a kind of "whistle" but it goes away with more rpm and ive sprayed carb cleaner everywhere without a change in rpm so if there is a vac leak i cant find it

what do you guys think?

 

well i don't even know about that. May be someone !!

 

i hope so..i posted on another forum too hours ago and you are the only one to respond lol im a member of some atv forums and i could have 20 replies in a hour...these ford forums are slow

 

Concern started or appeared quickly, meaning it didn't develop over some time?

Being your hearing a whistle, without any changes with a detailed spray, might look into the IAC, or possibly EGR. PCV as well. When it's running and you unplug the IAC, do the RPMs drop off? Engine temp reads?

For the insufficient Coolant/temp to go closed loop, low engine temps would cause a more rich condition and never enter closed. Could possibly be the sensor or a connector issue. If the engine temp is actually low, that needs to be addressed first to help correct a rich condition when heated.

If you have a long tube, hose etc. place it near where you hear the hiss and try and locate the general area,,

 

well i owned it for maybe a week before i noticed the whistle(i would have heard the whistle during that week so im not sure if it just wasnt doing it for that week)...i could never hear it while at idle in or out of the truck but yesterday for the first time i heard it while outside the truck with hood open before i did the carb cleaner vacuum check(btw i did a control test and took a vac line off and i litterally had to spray into the line direstly for any slight rpm change so i dont trust that test anymore, on this truck anyways)it sounded like it was coming from like around the middle of intake to back around the firewall

as for the insufficient Coolant/temp, when its cold my fan is on, ive never seen it slow down or stop, it slows down obviously with rpm but i would think when cold it would really be spinning like it was fully engaged..is that normal?

 

also, my temp gauge doesnt work and ill have to unplug and check on the iac when i make it outside

 

soo..i went to the gas station(4 mile round trip, and left the truck running so i didnt have to STOMP on the gas and look like "that guy" with a pos truck), the truck started right up as usual since its been sitting....so i whistled my way home lol it only whistles around 2k rpm im guessing and poped the hood, it was idleing fine, i unplugged the IAC and the idle dropped but wasnt acting like it was going to die or anything, when i plug the IAC back in it idles up then goes back to "normal"

 

Possible the IMRC (intake manifold runner control) is hung a bit causing the whistle and may help to set the fuel/lean codes. Low engine temp, rich mixture conditions. Most minor vacuum leaks tend to be noticed or develop at idle or just off idle. Again, if you can use a listening device and work around the engine to help point to the whistle origin, might help with a direction. An external vacuum leak should be reasonably easy to pick up.


If the scan tool they used has the capability to access the system PIDS ( parameter information display) they can look and see what the engine running temps are, or, what the PCM see's..

 

thank you, i guess ill go to harbor freight and grab a cheapy..

 

Cheaply?

If you mean scan tool, the low cost diagnostic tools usually don't have any expanded or functional test capability. Just mainly code readers. A decent size and length flexablable hose works well to pick up engine noises too..