rough Idle, could it be caused by the Mass Air Flow Sensor? my truck only when its cold in the moring idle jumps from 500 - 2300 and sounds like a harley, what would be the problem, after it warms up it runs great the rest of the day. I just wanted to know cause the Ford Dealership is trying to say that my intake caused the failure of my MAF. If I did replace it, it would be with out warrenty because I have the aftermarket intake. Plus they want like 250 in labor to repalce it not including parts. They also are charging 350 to replace a tensioner $71 and a belt $91, and the rest is Labor. i feel cheated. Please help with my problem, thanks
The Mass Air Flow sensor definitely would do that. The intake would cause the failure if you over oiled the filter and it screwed up the MAF. The MAF is easy enough to change as you should well know. The belt and tensioner are about an hour or so to do if you want to do it yourself.
You can replace the MAF in about 10 minutes I don't understand why they are going to charge you $250 in labor. It sounds like a rip off to me. These are all repairs you can do yourself , since they are saying the warranty is voided. If you can't do the work yourself atleast find another dealer to deal with.
Clean the MAFS with some CRC electrical contact cleaner if it is dirty but the MAFS will not change your idle at all.
Sounds like your IAC is the problem. Your IAC is responsible for your RPMs when you are idling or coming to a stop (When ever you are not pressing the throttle). They can not be cleaned or fixed so you have to replace them. I forgot how much they cost but I think under 50 bucks. It's not un-common for the IAC to kick the bucket, especially if you are using a K&N or other oil based air filter.
On a side note, sounds like that dealership is trying to screw you over BIG time.
It's located on the throttle body. It has an electrical connector, 2 screws, and a gasket. Unplug electrical connector, remove the 2 screws, remove IAC, remove gasket.....put back on in reverse order. (At least on my 02 3.0L)
After cleaning your MAFS (Gentle sprays will do.....don't spray the **** out of it from 2" from the spray bottle...you can damage the sensor...also make sure you let it dry for a minute before re-installing) and installing a new IAC, I would remove the negative battery cable for 15minutes so the PCM can relearn everything from a newly cleaned and new sensor
Man if its MAF clean it with brake clean and itll be fine. Belt and tensioner is very easy to do and you can rent the tools to do it. IAC would crap on its own and would be very easy to replace. F the dealerships man.
Pays 30 minso replace it. Its very very easy... Heres a pic of it...
I dont even remember been 4 years, put 70000 miles on it with the intake on. Just remember all I do is every 5000 miles wash it off with water and replace. Thanks guys yall are a great help I will get my truck back tommorrow and try and clean the MAF if that dosent work I will replace the IAC and see. This is the worst dealership I have ever been too.
Last edited by manic5_2001; 04-11-2007 at 07:50 PM.
Reason: more info
for the diagnostics run on the truck............. or so they say, I am going to the manager tomorrow and also price checking parts from random dealerships around the country. i plan on calling dearborn michigan to complain this is bull **** how they treat customers.
I very much doubt it's the MAF. I would clean it, but I wouldn't replace it. At least not up front.
The IAC is a more likely cause, but then again the poor idle condition seems to happen only when the engine is cold, which makes me think it's not the IAC.
A bad ECT might cause a poor idle like that, as someone noted, but that's usually a warm engine issue.
If it were mine, I'd pull the intake and see what the gaskets look like. I've been hearing more and more about SOHC intake gaskets causing idle problems and lean conditions, most particularly when the engine is cold. Ford even re-designed the intake gaskets, making them beefier for a better seal.