Knowledgable truck guys....
10-10-2009, 09:43 AM
#11
Nontypical Buck
Join Date: Mar 2008
Location: Henderson, KY
Posts: 1,760
I agree with the MAF sensor as a possibility. What engine does it have and is the check engine light on? The mass air flow sensors a lot of times will not set a trouble code/check engine light. The 5.3 and 6.0 liter engines have had problems with intake gaskets leaking vacuum as well. We see more problems cold than hot. When they are cold they leak more and run rough and wont idle well, then when they warm up they expand and seal again. If you have codes read somewhere see what they are and let me know, I can further assist you in the diagnosis. If it has a p0171 and p0174 it is an intake gasket leak. You will probably have p0300 missfire codes also. Let me know if you need more info. You can PM me if you want. Good luck.
To the op: If you wanna check this before taking it anywhere, you can have someone spray carb cleaner all around the seal of the intake, and if its leaking, you will probably be able to easily tell. In my experience with GM and intake leaks, I have been able to hear the leak, but yours may be small enough that its not whistling. But then again, your symptoms are pretty large, so Im not sure...
either way, you are probably off to a good start now. Just narrow it down.
but ill get a car computer from a friend of mine and check and see whats wrong....mainly the MAF...seems to be a constant..
10-10-2009, 02:55 PM
#14
Fork Horn
Join Date: Oct 2007
Location: Horseheads NY
Posts: 403
I believe its either the MAF, OR it could be your IAC Valve AKA: Idle Air Control Valve. It controls your air intake at idle, allowing your engine to consume just the right amount of air to keep it running smoothly.
being that the issue is only happening when you are not giving it gas, I would say almost 100% that it is air intake related, now you just have to figure out which part of the system it is. Not too complicated though.
Read up on the IAC and its location on the web, and see if you can find it on your truck. I imagine its on the bottom side of your throttle body(most are). You can either take it off and try and clean it up a bit, or tap on it lightly to see if you can free it up. Cleaning out your MAF may help as well.
Just try a few of these things BEFORE you go out and spend money on it
Derek
being that the issue is only happening when you are not giving it gas, I would say almost 100% that it is air intake related, now you just have to figure out which part of the system it is. Not too complicated though.
Read up on the IAC and its location on the web, and see if you can find it on your truck. I imagine its on the bottom side of your throttle body(most are). You can either take it off and try and clean it up a bit, or tap on it lightly to see if you can free it up. Cleaning out your MAF may help as well.
Just try a few of these things BEFORE you go out and spend money on it
Derek
10-10-2009, 06:07 PM
#15
Fork Horn
Join Date: Aug 2007
Location: Kansas
Posts: 282
Just a heads up, there is no IAC on this year of truck so don't worry about checking the IAC. The vacuum leaks on these engines can "not" be heard in my experience. You can spray carb clean or flamable brake clean around the front and rear of the intake. There is foam at the front and rear that make it hard to get the spray where it needs to be but it can be done. Need anymore help let me know.
10-12-2009, 09:11 AM
#17
Nontypical Buck
Join Date: Mar 2008
Location: Henderson, KY
Posts: 1,760
Just a heads up, there is no IAC on this year of truck so don't worry about checking the IAC. The vacuum leaks on these engines can "not" be heard in my experience. You can spray carb clean or flamable brake clean around the front and rear of the intake. There is foam at the front and rear that make it hard to get the spray where it needs to be but it can be done. Need anymore help let me know.
Thanks for the correction!
10-12-2009, 10:24 AM
#18
Fork Horn
Join Date: Sep 2009
Location: maine
Posts: 139
as a ford tech i see plenty of iac problems and normally has nothing to do with temp, plus as stated that truck has no iac. I can say that i did just do intake gaskets on my own truck that is the exact same truck as yours for the same reason. also se this PLENTY on fords as well can now do them in my sleep, also you may not want to try to clean the maf as most of them if not already bad will be ruined by most carb cleaner and you will have multiple problems then.
10-12-2009, 10:28 AM
#19
Nontypical Buck
Join Date: Oct 2007
Location: central and east texas
Posts: 4,894
i didnt read any of the post but i would say it is the idle air control, or idle control whatever it is called on ur truck..if ya tap it with a screw driver a couple times it wwill usually activate it
10-12-2009, 07:47 PM
#20
Fork Horn
Join Date: Aug 2007
Location: Kansas
Posts: 282
as a ford tech i see plenty of iac problems and normally has nothing to do with temp, plus as stated that truck has no iac. I can say that i did just do intake gaskets on my own truck that is the exact same truck as yours for the same reason. also se this PLENTY on fords as well can now do them in my sleep, also you may not want to try to clean the maf as most of them if not already bad will be ruined by most carb cleaner and you will have multiple problems then.
Depending on what brand of carb clean or brake clean use the ones that say sensor safe.
