2005 Mercury Mountaineer Questions!?!?

[Bignosdaddy]

Hello Everyone!!

I'm new here, and I got some questions, along with helpful tips for 2005 Mountaineer!

First off I have a 2005 Mercury Mountaineer 4.6L V8 with 204,000 miles on it. I have owned it for 4 1/2 yrs now. Six payment left and its all mine!!
I have replaced all four wheel bearings/hubs, put a new egr valve, new upper, and lower ball joints, #1 coil pack, and #1 plug last year.
This year so far I have replace the mass air flow sensor, Throttle Positioning Sensor, Oil Sending Sensor. Now I have to replace the muffler since I just found about a 50 cent piece size hole in the side of it.
With all that done now all of the sudden it is sucking the gas really bad!! I travel about 25 miles round trip to work, and on my miles till empty. It will drop almost 40 everyday!! That is killing me on my gas bill. Also when I am at a stop light or stop at the stop sign waiting my turn. The vehicle is shaking or stuibbling, and between 40 to 60 mph it acts like it studders and shakes again. There has been even times when I have come up to a stop light or stop light the rpm's just drop to 0 and it stalls on me. All I have to do is put it in Nuetral and will start right back up. I have done 2 weeks of research online and can't find no help no where on what it could be now.
So I am hoping someone had had the same or similar problem here, and can help me out. Thanks for any and all imput on this situation.

 

[silverfox103]

Hi Big Daddy

Welcome to the forum. First of all, with 204K on your Mountaineer, we've got a lot to learn from you. Just for a guess, as it just happened to me today, would it be a coil pack?

Good Luck

Tom

 

[Number4]

'04-'05 have the drive by wire throttle body. The throttle body valve is prone to sticking due to oil build up. Doesn't have to be much. It usually doesn't become a problem until you disconnect the battery. At which time the computer thinks the system is new and no longer compensates for the crude.

Follow these two videos, in order, it should fix your issue.

Clean your TB:
https://m.youtube.com/watch?v=JPNnHU6PYbo

Re learn settings:
http://www.explorerforum.com/forums/showthread.php?t=396533

 

[extra-medium]

Have you checked O2 sensors? Is it throwing any codes at all or has it only been since you replaced the parts that it started acting up.

 

[JakePSD]

Check codes first thing. Sounds to me like you should replace all 8 spark plugs.

 

[Bignosdaddy]

No it is not throwing any codes at all. The only code I got out of it was the mass air flow sensor code, and I was already at Autozone at the time. So I went back inside and purchased it and put it on right there in their parking lot, but that didn't help at all. Now the battery did die in January and it was about week before I could get a new one, because I was out of town for work. I wonder if that would habe messed with the computer? My oldest said he started it once to take it to school and it said fail safe mode, but I have never seen it. So I can't confirm that.

 

[JakePSD]

have you checked the fuel pressure? Maybe the fuel filter is plugged. just throwing ideas out there.

 

[Bignosdaddy]

No I haven't check that yet. I was going to clean the throttle body, and if that didn't work. I was going to check that out. If all that didn't work, then I guess I will order plugs and coil packs

 

[Number4]

TB cleaning is $10 in parts and 20 minutes of time.

 

[Bignosdaddy]

Ok thanks, and that's this weekends project due to my work schedule this week.

 

[Bignosdaddy]

Ok, well I took the throttle body out, and gave a good cleaning, and wiped it all down. Put it back together and took it for a good hr spin. That helped considerably! No stalling out at the stops signs and red lights. The shaking isn't as bad sitting either, but it did not get rid of the studdering in power between 45 and 60 mph. That and it still sucks the gas down! So today's project is to the replace the muffler. Since I found a nice hole in it, and it's starting to get loud lol. So now I'm back to square one with this problem.

 

[LMHmedchem]

Ok, well I took the throttle body out, and gave a good cleaning, and wiped it all down. Put it back together and took it for a good hr spin. That helped considerably! No stalling out at the stops signs and red lights. The shaking isn't as bad sitting either, but it did not get rid of the studdering in power between 45 and 60 mph. That and it still sucks the gas down! So today's project is to the replace the muffler. Since I found a nice hole in it, and it's starting to get loud lol. So now I'm back to square one with this problem.

If you cleaned your throttle body and replaced your ERG and MAF sensor, you really do need to reset your computer. Follow the instructions posted by number4 in the third post. Your computer probably reset when you had the batter out for a while, but you have done more work since then and there is a "proper" procedure for the computer reset, meaning what you do when you first start up afterwords. I would definately replace all of your plugs, your air filter, and your fuel filter if you haven't done any of that yet. Do all of your work and then do the computer reset.

LMHmedchem

 

[Bignosdaddy]

Ok sounds good Thank you Sir much appreciated! The fuel filter is the next on the list, and now it's time to look at plugs and coil packs then.