4.0 power loss?

[Trapper14]

This maybe sorta long but please bear with me. My engine started hesitating about a year ago, hit the gas and no acceleration for a second or so, I thought it was the clutch skipping cause thats what it felt like. I Threw in a Centerforce dual friction (which I love) and it still was there. I decided to replace some electronics. I purchased
autolite platinums
generic plug wires
cleaned maf
cleaned throttle body
cleaned KKM
replaced fuel filter
replaced PCV valve

everything was back to normal and ran wonderful.

Now not even a yeard later, maybe 79 months, its doing it again same hesitation same loss of power, I mean this thing is gutless!
At startup sometimes it is very rough, and threatens to stall but never does.. Very rarely it backfires under acceleration.
What could it be? I spaced the plugs properly but this is nuts I get around 16-17 mpg between highway and town.

BTW I have a 5 speed if u didn't already guess.

PLEASE HELP!

 

[Commtech]

Have you checked for Vacume leaks?

 

[Jon97]

Have you changed your oil lately? I have 4.0 and it was sluggish and hesitant like you described. Then I changed the oil and it got better. Not totally but it seems to run smoother than before and with more consistency.

 

[SteveVB]

coil pack

I would check for vacuum leaks also.

Also may want to have the coil checked out - or replace it. Even if the coil pack checks with the vom tests in most service books it can still be weak under load, I had a coil pack that tested fine with all of my shadetree tests I could do, we couldnt find any problems but we had one. Took it in they put it on the scope they looked at the spark under load and road conditions and found the coil pack problem.

 

[Trapper14]

coil pack huh? never thought of that how much are they?

 

[V8-X]

Coil Packs should cost you under $100. Depends on if you want a stock replacement, or if you'd go for the store brand. Check out this website, they usually have good prices on stock Ford parts. Hope this helps.

http://www.fordpartsonline.com/

 

[410Fortune]

Fuel filter, 02 sensors.............

How many miles do you have?

The wrong thing to do is start throwing $$$ at it.

common causes for what you describe:
leaking lower intake manifold (tighten the bots = temp fix)
dirty fuel filter

weak 02 sensors

weak fuel pump

clogged cat converter (converter gets clogged when raw fuel is dumped. raw fuel is dumped when 02s go bad, or vacuum leaks, computer tries to compenstate with too much gas)

also a faulty fuel pressure regulator

If you have spark at all 6 then start looking at fuel pressure and fuel system problems.........

 

[NOTAJP]

Replace your platinum plugs. In my autoparts store, I have seen so many plugs return. Only the new engines really work with the platinum plugs. Change your plugs with $.99 Autolites every 12-18 months. Has worked great in my X. If you buy cheap fuel, change your fuel filter regularly also.
Just my 2 bits....

 

[94expo]

fuel pressure regulator - fuel pressure regulator - fuel pressure regulator - fuel pressure regulator

 

[Trapper14]

lol expo, well I went out and bought a coilpack to start with. dam t-bolts are alls tripped now I gotta get a screw extoractor. Whats this fuel pressure regularot ru speak of, hard ot replace?

Thanks

Sean

 

[Trapper14]

finally got all those bolts off after 2 broken drills, and 1 broke bolt extractor I discovered the #2 to be VERY VERY drity, with black buildup inside the connector on the coil itself, so this might be the problem after all!

Sean

 

[Trapper14]

on further examination... I have been experiencing coolant loss, and about 1 quart of oil a week consumption. hmm weird. I take off oil filler cap only to find my fears conformed... milky tan substance. I need a new engine right? cause I got NO money, nothing and I need this car for college, my parents are broke too... am I screwed?

 

[Bigred08046]

head gasket?

Classic head gasket signs. Have some one do a simple pressure test. Attach a radiator cap with a pump. Pump up see where leaking! I hope it's an intake manifold gasket rathen then the head gasket.. let us know.

 

[Trapper14]

is it possible to buy one of these pumps? I hate mechanics.... lol