Idle & Loss Of Power !HELP!!

[Jobesmind]

Okay I have lost my mind on this one.

Working on a 99' Ford Explorer (4L SOHC), Just finished a serious brake system replacement. On the way home today the XT started instantly hessitating and idleing very rough (Like a single plug is missing every now and then) And a ive got a nice loss of power. No codes stored into the system.... Wife said the Check engine light came on once but went out within a minute or shorter.

After checking all the obvious (plugs, airfilter, wires, ect.) I came across an odd feature, unplugging the MAF sensor resolved the problem and the idle smoothed right out (better then ever). As soon as you plug it back in, it resumes the rough idle. Just looking for some thoughts. Not sure if it is dirty or damaged because ive never seen a new or clean maf.

Help me Mr. Wizard!!!!!!!!!!!!!!!!!!!!!!!

Don't wanna really buy a new one )
Cardone P/N 74-50011 $87.00 Core & $135.99 Sale price for reman. MaF

 

[aldive]

I would run a scan to see whats going on.

Another thought would be a can of Sea Foam through the intake.

 

[yosh18981898]

Take the MAF sensor out and clean it with sensor safe carb and choke cleaner (gumout). This is a common problem with Fords, especially the 4.0
V-6. Me and several other members on this board have had the same problem and fixed it just by cleaning it.

Oh, and welcome to the board. Like most members you suscribed to the board to fix your X, but keep looking around the board and you'll quickly get bitten by the mod bug and pretty soon your X will look like one of the feature trucks on this board. Thats what happens to most people who join, anyways.

Good luck with the X,

Eddie

 

[Jobesmind]

Okay It's tuesday now.. Cleaned the Maf out (IAC was already replaced during last service) checked everything again and still no stored codes....

Drivability is horrible alot of hessitaton and still a rough idle... but no Check light and no codes.... fuel pressure tested good, coil tested good..... Im at a loss.

pulling it into a performance shop (They deal with these mystery's better 'just my opinion') I dont have the equipment to do a live test... So I'll have to pay )

Also Does anyone know of a mod kit for the timing set on the 4L SOHC? I am done with the chain noise lol and the dealer... $600 a pop and had the service 3 times (Im not even sure they fixed the tensioner).. never did stop the chain rattle..

Ill keep everyone updated..

 

[Jobesmind]

Updated#########

Just got the XT back from the tech...

Are you ready???

The odd idleing and hessitation was caused by a single spark plug fouling when hot.. Thats it....

Causes all the same problems as failed MAF, IAC, Fuel pressure, ect. ,but without any Stored codes..

Hope it help someone else out there )

 

[duckdog27]

My 94xlt does the same...

When I turn the engine on when it is hot I have extreme hesitation and no power. I thought I had fixed it with a new EGR valve/EGR Sensor, but obviously not. So you are saying it is a hot spark plug misfiring? I changed my spark plugs about 1000 miles ago and my XLT keeps on doing it! I also replaced the Fuel pressure regulator, cleaned the Mass airflow sensor, and I still get hesitation and no power after turning on the hot xlt. Did you just replace the spark plug?

 

[Billy177]

you did get the manifold gasket recall performed right? cause if you did not that is your prolblem

 

[duckdog27]

No, I never did get the lower maniforld gasket recall! When was that. I have only owned the XLT for a few months. My brother in law bought it in 2000 and he mentioned that a technician said that the lower manifold gasket is leaking oil and coolant. Could that be the problem?

 

[Billy177]

i had the same symptoms with mine and the recall fixed it now it has much more power, better gas milage and idles fine. i dont rember if it is a recall or a tsb but just tell ford about it and they should fix it for free. there is also a new chain tensioner included with this also

 

[duckdog27]

What is TBS? And with a 94 how can I have Ford replace the part for free? Do I call the local Ford dealership? Any information is very much appreciated.

 

[Billy177]

technial servie bullatin and it is only for the sohc engine