Help me!!!!!!!!

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My name is Billy And i have some problems with my F150 truck. I have a 4.6 sohc and i have done some stuff to it like i put a mac throttle body 75mm on it plus i chipped it, ram air hood, underdrive pullyes, throttlebody spacer K&N cold air intake also. Well here's my problem it's been surging with the idle and i can't fig it out at all!!! plus now it sounds like it has a leek or something it's hard to explain, like when i take off it putts then it catches up and takes off, but wait i thought it was an exhaust leek but it's not!!!! it' is something else i don't know what can someone help me please!!!!!!!! My number is 215-651-2529 I live in Ambler Pa. And i'm getting restless. please someone if you have had the same problem or know what to do please call or write me!! my email is nymphoman77@hotmail.com

thanks Billy

 

Hello Bill,
I'm not to far away from your area.
I suspect you upset things a bit with the larger Throttle body.
The combinations you have might be causing problems so I would start with a warmed up engine, remove the Iac plug with the engine running and see what the idle does. If it doesnot drop a good amount, check the throttle stop setting and make sure it's adjusted to a low idle of about 550 to 600 rpm.
Then restore the IAC plug. The idle should go up indicating the IAC is able to control the idle.
Reboot the computer, start the engine and drive at least 5 miles to allow the computer to relearn to some degree.
Then go from this point so at least you know what the IAC is able to do.
The IAC is the idle air controller. It controls air bypass around the throttle body and is mounted on the outside with a connector attached.
This is only a suggested start to see what the affecting issues are.
You may even end up restoring one part at a time just to see what is going on.

 

omg thank you for answering my call for help do you think that is the problem? i don't know where the iac is on my truck? do you think you could give me a call and explain?

 

I would suggest you go get a Haynes manuel for you truck as you will make good use of it. Look on page 4-14, figs 1.2/14.3 and the text.
Somene here will post a picture for you to see i'm sure.
It's right close to the new throttle body and held on with 2 bolts.
Make sure you don't have a gasket vacuum leak on the New body.

 

thank you for your advice i will do you what you say and i'll get back to you in a couple of days

 

You say you have a 4.6 so here is a favorite of mine by Grinomyte ...

http://www.fordf150.net/howto/throttlebodyclean.php

and page 2

http://www.fordf150.net/howto/throttlebodyclean2.php

 

dude i've been asking anybody if they could help and you did!!!!! thanks man!!!!!!!

 

did what you said got a book and today i took the whole intake manifoldoff and that was a job let me tell ya, But I got through But wanted to tell you the progress i have to tell you something, that **** was dirty as hell the IAC valve is shot i 'm getting another tomorrow and it's $58.62 At C&C Ford. But i hope that this will solve my problem. So i can move on to get ready for the shfter and new Heads Commin'. I will wirte in tomorrow and let ya know if it was it?????

Billy.....

 

what heads did u buy for ur truck?

 

Thanks for the feedback, we appreciate it.

 

Ok This is what I did, First I got a new IAC and Then i took the entie intake manilfold off cleaned it but then the high idle came back then it was misfiring, then i replaced all of the coils, then the truck is running like a champ i think that everything is cool, well the service engine light comes on!!!! Ok I have followed evertyhing the dtc codes were comming back as. Now it's saying and now I'm about to rip my hair out!!!! I checked the injectors they are fine. fuel relay dvr failure was another DTC code that showing up along with SYS TO LEAN? So i replaced it and the high idle is back and the same DTC codes are back from before so nowI turn to you guys for help!!!!!!!!!!!!!!!!!!!!!!!!! What Do I do NOW??????????????????? Please help!!!! by the way i roushe headers coated!

 

What are the actual codes?
The codes donot tell you what parts to replace.
Not knowing anything about how the systems work is putting you in this position.
I don't mean anything derogitory by this but you have to understand that mutiple codes has to be understood and sorted out because some can be related to the point that finding the real fault can clear more than one problem and codes.
Overall I still think you have a vacuum leak even if it is a crack in some intake part.
The lean code is telling you that the computer sees the oxygen content out of range and tried to correct it but can't, hence the code for it.
This fault upsets the idle air into the engine ( unaccounted for air) and is detected in the exhaust as well.
I don't know how else we can help through this meduim but take educated guesss based on your reports. If your missing something we have no way to tell it.
Good luck.

 

i HAVE CHECKED EVERYTHING THAT YOU GUYS TOLD ME TO DO I'M WONDERING IF I HAVE A BAD SENSOR???? OR THE CODES ARE WRONG? BECAUSE I HAVE A CHILTON MANUAL AND I FOLLOWED WHAT TO DO I JUST DON'T GET IT MAYBE THE TUNNER IS BAD OR THE THROTTL BODY IS BAD OR SOMETHING????

 

75 mm Throttle Bodies have been known to cause a Lean Condition. If you still have the factory original re-install it. If that doesn't improve the situation post the actual OBII codes and we'll try to help you.

Good Luck,
Stay Cool,

Bill

 

Disconnect your battery for 5 minutes to reset your computer and then wait to see if the service engine light comes back on. This should reset your parameters and let the engine learn again (takes about 100 miles).

If you do get codes, please post them here.