My thoughts are as follows in order.

bad gas.

Too much timing advance. RETARD!! a few degrees

maybe time for a valve lash adjustment?

btw, its called a "pcv valve". pvc is a form of plastic.

--NAH2323
Fuel injection junkie.

 

Bluegrass - that makes a lot of sense. I have read your other posts and you seem like you kow what your talking about. I will be taking the chip out of a test run. I do get some pinging (w/o trailer) on some of the larger hills near me so I will test it there first.

Also, what I thought was the egr valve I know think is the TPS (throttle position sensor) based on the pics in my haynes manual. I will fix the broken stud, give it a syn. oil change and a new K&N filter. Mine has about 60k on it.
My plugs and wires re about a year old and only have about 5-10k on them.
Autozone has the egr vavle for about $50 so I may change that as well.
Can I buy the seafoam at auto zone as well?

 

My thoughts exactly.

 

DEFINETELY try this first. Take your throttle body apart down to the intake runners. Be careful not to drop any nuts/bolts down into the intake or under the intake runners...hard to retrieve once theyre down there.

Do a search in the Engines forum for "Rough Idle Problem" under my screen name "Green_98" That thread has all the pictures and explanations needed to do this job.
Youll need:
-4 cans of carb/intake cleaner
-Cotton swabs or an old toothbrush, etc
-3 gaskets from Ford---should be 10-15 bucks total
-allow about 4 hours to do this

It's not hard to do, just hard to reach and time consuming, but overall not that bad. It made my 98 4.6 w/ 75,xxx run like brand new!

 

Well, I pulled the chip completely out and the truck ran pretty good. I didnt hear the little bit of pinging I usually hear on the highways. I havent tried ulling the trailr yet without the chip but so far it seems to be ok. I will still do the port cleaning and the t-body cleaning as well to see how it runs.

 

I haev a 2000 F150 that had the same prolem.
Turned out I had a slight mis-fire on #8
After replacing the coil & boot, and running a better grade of gas the problem was gone.

Hope this helps.

 

Lost_One - How did you determine you had a miss fire?

 

BLANK21, if you are gonna use the chip you should probably be using slightly higher octane midgrade gas(or even premium) even if it doesn't say it is nessecary for the chip to work properly. However I doubt that you would be able to tow much with the chip, even with premium. I'd try cleaning the egr valves like others suggested as well, if they are nearly plugged, then your truck should run like new after the cleaning.

 

I agree with bluegrass, plus that vacuum leak ain't helping

 

Well I found it by mistake.
I never really noticed the problem till I was either heading up hills or pulling my trailer.
I took this to my dealership, but they found nothing.
After talking to one of the shop guys, he informed me of this.

Seems the Boots on the coils can split, and in some cases wont throw the chech ENG light on. So I had 2 choices, pay they $900.00 to maybe find the problem. or do it my self. (Yep, i did this myself)

 

Well after my drive home the truck was running very strong. I was hitting the hills on the highway at 80+ to try and get some pinging but nothing.
I am still going to clean the whole t-body and the egr ports.
I have been running 93 octane since I put the chip in.
As for the vac. leak I have to look into that. Either way the broken stud will be fixed.

On a side note - hows this for prices
Brought my wifes windstar into the dealer for an oil leak, a grinding in the steering column, squeaking brakes, the engine light on, and it was pinging also.
heres what they told me.

Oil lek is covered by warranty, small pin hole in timing cover and lower intake gasket

Grinding in steering column is just OUTER tie rod ends. $300+ to fix
squeaking brakes - front rotors need to be cut, and it needs rear brakes $500+
pinging is a bad MAF sensor - it is reading I am below sea level $300+.
All in all they want over $1200 to fix everything.
I can do it myself for these prices
outer AND inner tie rod ends both sides Lifetime guarentee - $94
brand new front rotors - $60
new rear shoes - $30
cut rear drums $12 - $6 each
reman. MAF sensor $135 with $87 core charge
Their price $1200
My price $244
Are dealers scum or what?

 

Blank,
My Dad told me a story about a television repair man (whats that) that charged him $50.00 to adjust 1 screw. This was back in the 60's mind you. He indignantly asked "Why so much to turn 1 screw?". The response was " $49.00 is to know which screw to turn.".

If you find a good dealer and have the means to support them by all means do. Dealers have a big nut to crack in regards to overhead, insurance, wages, and so on. There are a few dealer techs on this site that volunteer their time and info for free.

Unfortunately there are also some bad dealers that wll rip off anything that walks, even a few that can't. i was lucky enough to find an ex dealer tech that went out on his own. I try to do as much as I can myself and this site really helps. It is nice to have Randy to fall back on, as I could never afford the investment he has in computer tools alone.

Congrats on fixing your problem and good luck with the Misses auto,

 

I agree the guys on this site are unbelieveable. I do not knock the employees of the dealership, but I cant see how they can justify $500 to cut front rotors and replace rear drum brakes.
$72 in parts and $428 in labor. Even at $100 an hour for labor which is very high, it should only take about an hour or so to do the whole brake job. I can do it that fast and I dont do it every day.
Thank god for the guys here with thier knowledge and certain auto parts stores that have free loaner tools.

 

Amen.
The closest dealer to me charges $75.00 apiece to cut front rotors on my 98 F150. They have a special machine to cut them on the vehicle. I guess they can't get the rotors off easily either.

When I was in the garage which was long ago we always cut the drums,rotors, repacked wheel bearings, and so on for every brake job. The boss always claimed it was to prevent comebacks. It didn't hurt his bottom line either.

 

On my truck I have slotted rotors so I dont need to have them cut anymore.