Engine running rough, while air is on!

[DonM]

I had this on another board, didnt get much help.



Ok this has been an on going problem for a while now. I think im getting closer to finding the problem?

I noticed when i have either AC, or defrost. The engine runs rough and the whole vehicle vibrates. The tail pipe rattles and vibrates the most. The muffler and pipes were just replaced not to long ago. Even before the new muffler and pipes it all ways did this!

Im not sure how to explain this, but here goes. When i turn the air on, i here a clicking noise coming from under the hood. I guess this is the engine going thru cycles? When this happens i notice a small power like surge and then the vibrating starts. When the cycle is over, the vibrating stops! This is while in drive but at a stand still, if i were to put it in "park" the vibrating would stop.

I was waiting in line at the car wash today and it has been bothering me. So id like to finally get to the bottom of this.

EDIT: Iac is new, also have a new PCV.


Thanks

Don

 

[jimbo74]

sounds like your idle speed isnt adjusted properly.... but i am not sure if the idle speed is adjustable on the xs or not....

 

[DonM]

I dont believe it is?

 

[vbtruk]

ohhhhhhhhhhh **** i get this TOOOO!!!!
But when i first start my car and turn the air con ON the car will start to vibrate and the engine seem's like it is almost going to stall but it doesn't, this happens in park at idle but not drive BUT it doesn't alway's do it some days yes and some days NO! so whats up i cant figure it out!

 

[vbtruk]

Rough IDLE

Hey guy's my CEL just came on again and i went to FORD and they told me it was the Intake GASKET's 6 of the round one's and a manifold gasket or something, anyway they want $130AUS in parts total and $230 for Labour so do you think i could do it myself or just get them to do it????
The CEL was triggered due to a vaccumn leak in the intake and this is causeing the rough idle even more so when AIR is! Ford mentioned this to me before i even told them about the rough idle!

 

[Strike12]

The idle speed is adjusted through the IAC . When you turn the the a/c on , it puts more load on your engine and will decrease the rpms ,the computer senses the rpm change and tells the IAC to open more and compensates for the lower rpm . Ill assume since you replaced the IAC already , Id check the connection to the IAC , make sure its not corroded and has good contact , make sure the pass through air passages arent pluggged , and it also could be a faulty replacement , it does happen often. Does your CEL come on? Check to make sure you have the correct voltage to it. You can find the tests in chiltons and haynes repair manuals . Hope this helps . Let us Know what happens.

 

[TPLYNCH]

VBTRUK, do you have the SOHC 4.0 engine, not the V8? If it's the 4.0 then yes, the O-rings are know problem along with the cam chain tensioners. Search for 00M12 and 01M01. These are owner notification programs that extended the warranty of the defective parts up to 72K miles. So, as long as you have less than than that, DO NOT PAY! FORD PAYS. They did for member Swede in Sweden who had the exact same problem. Did take Ford there 6 weeks or something crazy like that to do it, but they did.

 

[vbtruk]

TPLYNCH, i do have the 4.0L SOHC. the cam chain tensioner has already been done by ford but the Gasket can't as my car is out of warranty so i can do it myself?
How about clearing the code and do i need to get a sealent to stick the gasket's
thank's.

 

[TPLYNCH]

The writeup (with pictures) is on the second page of the attached thread. Several people on the board have done it themselves now. Good Luck!http://www.explorerforum.com/forums/showthread.php?threadid=61152&highlight=cold+idle

 

[vbtruk]

Hey TPLYNCH your a champ i'll grow some balls and do it on monday i'll let you know!!!!!!
thanks

 

[vbtruk]

All Credit to MIKEH

Hey thank's MIKEH i followed your write up and replaced the o'ring's and intake manifold gasket's it was too easy took about 4 hour's and i did a better job putting it back together than Ford who replaced them the first time!!!! yeh the new silicon blue o'ring's are of much better quality than those plastiky green ones. so thanks again mike for that post, and when i turned my air con on the truck idled and purred like brand new.
I saved $230 doing it myself.

 

[vbtruk]

Hey TPLYNCH the truck was fine yesterday but it started idleing rough again the CEL came back on???? i tightened the screws real tight and didn't use and oil or grease on the rubber gasket's so why are they still leaking the vaccum seal and how can i fix it? maybe i forgot something can some one please help?????

 

[DonM]

*UPDATE*

Last week I installed an Apten Chip, it works great.

The engine has really smoothed out!! It's still not perfect, but close to how I think it should run. I have a question....

I noticed, when My X is either in Drive or Neutral, the engine runs very smooth now. But if I put it in park, the engine runs a little rough. Not as bad as it did before the chip. But enough to bother me still. So now what should I look at? Im not sure what could cause it to run rough in Park, but not in Drive or Neutral? Any ideas???

Btw, I just changed the Fuel Filter. The filter was kinda dirty, but not as bad as I expected it to be. I didnt notice any dif yet. Maybe I will?

Again, new plugs, wires, new MAF, new IAC, O2 sensors Fuel Filter.

Ive got it down to Vac leak, or a bad FPR?

What do you guys think?


Don

 

[Strike12]

Hey peeps , Have you checked the coolant sensor , it might not show its faulty , but could be out of range , ive had this happen and I posted my findings in another thread . Check to make sure its within range , ohms = temperature . It never sounded like you had a intake leak to begin with , although the write up on the change over was informative , I didnt think this was causing the problem. I still havent seen any codes posted on this topic yet , to really come to any reasonable conclusion . Please post the codes if you have a CEL , so we can work on this together . A code doesnt mean its faulty , it means , it didnt meet the pcm's expectations , so it could be another part causing the problem . If you post the problem your having along with the codes that were found , we could solve this ALOT faster. Just my 2 cents. Just trying to help.

 

[vbtruk]

hey strike Ford checked the CEL so i dont know what the code was numericaly but they said it meant there was a vacum leak and ordered the gasket's for me so i did it to save money! i get the haynes book tomorrow so i'll test the coolant sensor but i don't see how that would affct the idle it only idle's **** at cold start up and when she reaches operating temp it smoothes out and run's perfect! i was told this is the classic sympton for worn out intake manifold gasket's, IF SO is it better to have it done up really tight or have the screws looser and was i supposed to lube or oil the rubber gasket's upon installation as i noticed when i pulled the old ones off they were greased by ford who replaced them last time???
Thanks Strike!

 

[DonM]

Oh yeah, A/C compressor is fine.

 

[TPLYNCH]

VB, if you can get the exact code, we'd be able to point you in the right direction.... It may just be that a vacuum line came loose or cracked while you did the repair. Also, check and make sure there are not cracks or openings in the air intake tube running from the MAS to the throttle body. Also make sure your MAS is still plugged in.....

 

[vbtruk]

TP my Maf is plugged and all tubes are conected as i was very carefull with them Ford is trying to find the exact code for me now but he said they were Lean AIR/Fuel mixture code's which is what prompted them to give me the Manifold Gasket KIT! i will pull it apart again and look over it and post the code's when i get them.
Any idea's otherwise?

 

[Strike12]

If it was a lean situation , then you can use starting fluid , spray it around where the intake bolts to the heads , do it while its cold , if yu you notice any rpm change then you have a intake leak . A safer way is use water in a spray bottle , not as flamable . and if you notice excessive steam coming out the tail pipe , then you have a intake leak . It also could be a non seated IAC valve . Pull the IAC and make sure the little valve between the two ports is closed or centered. You can spray around the upper engine with starting fluid and if rpm's change you found the leak , BE CAREFULL , dont spray it on the exhaust manifold or the near the coil pack , it's extremely flammable .This test could lead you to a faulty vacuum hose also . A lean condition also could be bad o2 sensors , but usually isnt a problem on a cold start . Check the IAC gasket with starting fluid also . Remember be careful with this recommendation , stay away from heat , such as a hot manifold , and stay away from spark , like the coil pack.

 

[vbtruk]

CODES

Strike 12 it's definately the gasket's they are brand new so i am guessing that i didn't install them properly i pulled it apart again and cleaned it up but still the same thing so i went back to ford and they felt sorry for me i guess and did a free code read (usually $76) and came up with this: LEAN MIXTURE CODES PO174 and PO171 BANK 1 and BANK 2 so the only thing i can guess is that i did up the bolts to tight as i don't have a tourqe wrench and did em real tight, i am going to buy a tourqe wrench now and loosen pull it apart again and loosen em up a bit let you guy's know.