Ford V10 engine surging /lugging / shaking .....possible causes ??

[kratedisease]

I have a 2000 Year ford V10 chassis on a thor hurricane. The RV has 25,000 miles.

When we recently took a trip from New York to Nashville TN, I noticed that the engine surges a bit at idle.

Even driving off from a stand still ( like a red light ), the engine idle surging causes some minor surging of the transmission and drive-train and causes the motorhome itself to jerk a very small but perceptible amount.
The engine idle revs repetitively up and down ever so slightly but causes the coach to surge a bit taking off from a standstill.

I also noticed that during our trip, that on hard acceleration climbing a long hill that there was also surging of power from the engine and some surging of the truck drivetrain itself and the motorhome as a whole while climbing a hill
In normal driving all feels normal except some mild engine surging.

Additionally, When I press the accelerator down and the chassis downshifts on a long hill climb the chassis drive-train has a vibration or shake and feels like a rotating front load clothes washer spinning quickly with one leg a bit short and out of balance. It is a very rapid shaking in the driveline. If I ease off the accelerator this shaking disappears


I feel pronounced rotating vibration in the drivetrain /chassis shakes like a clothes dryer or washer with a short leg in the spin cycle. It is a rapid "tapping" sensation or rapid "shaking" or "lashing" sensation on hard acceleration with downshifting. as soon as I ease off the gas it disappears.

Any suggestions as to why this might be occurring ??

Thanks in advance for any replies and assistance.

 

[jyro]

coil pack gone bad, quite common these days.

 

[driftless shifter]

Or fuel supply. Could be as simple as a dirty fuel filter.

Bill

 

[scottydl]

Start with the basics... clean the throttle body & replace fuel filter, possibly replace spark plugs, wires, coil packs.  Almost all of those things can be done by the owner, if you are a tad bit handy and/or willing to give it a try.  They are all maintenance items that should be done eventually anyway, depending on the rig's known history and when the last time any of them were replaced.

 

[jyro]

coil packs  https://www.youtube.com/watch?v=eoFNmtKEse8

 

[kratedisease]

Thanks for all the replies !!  Very helpful. 

 

[kratedisease]

Any additional input is greatly appreciated.

If anyone has additional input, kindly please post it !!

 

[PJ Stough]

Does your engine have an EGR valve?  That would be my first guess.

 

[scottydl]

krate, how long have you owned your Thor and do you know any of its maintenance history?  (assuming you purchased it used)

EGR value and engine misfires would probably trigger an error code and your Check Engine light.  Has it come on at all?  If so, you can have the computer scanned (free at most auto parts stores like Advance Auto, Auto Zone, etc.) to see what that tells you.

If you are familiar with ignition coil packs, you can test those yourself too with a multimeter set to measure ohms.  Each coil pack represents two cylinders of the engine, so your motorhome's V-10 will have 5 coil packs all lined up.  There is probably a cover to remove to reach the coils.  With the engine running, measure the ohms between the two contacts on each pair of coils.  If any one of them has a reading that is substantially different than the others, it likely needs replacement.

I would still start with the fuel maintenance items... fuel filter replacement and throttle body cleaning.  I removed and cleaned the throttle body on my 1994 Thor with the 460 engine, and it (the throttle body) was pretty easy to access from inside the rig with the doghouse cover removed.  Disconnect the TB from the air filter housing, a few bolts, and the TB is off.  I'd explain more but Youtube can do that for me: https://www.youtube.com/watch?v=BXwqBf4cqic (not a V10 but gives you an idea) 

 

[jyro]

the ford V10 has individual coil packs, 1 per spark plug, since the wire fits through a hole into the top of the spark plug, it's usually just the wire, esp. with just 25,000 miles on the engine. The wires are 15 years old.

 

[PJ Stough]

Sounds like time for new wires whether they are the problem or not.

 

[scottydl]

the ford V10 has individual coil packs, 1 per spark plug, since the wire fits through a hole into the top of the spark plug, it's usually just the wire, esp. with just 25,000 miles on the engine. The wires are 15 years old.

Thanks for the clarification!  My description above was general for many engines, so I'm glad you are familiar with the Ford V10 specifically.

 

[OLDRACER]

Before you replace spark plugs on the Ford V10, you should do some on line research on the subject.

 

[Alfa38User]

Before you replace spark plugs on the Ford V10, you should do some on line research on the subject.

.... Especially that vintage (2000), paying particular attention to the torquing required on the plugs!!!

 

[jyro]

at 25,000 miles, mostly highway, I wouldn't even risk plug removal unless boots Didn't fix it. the wire to the plug on the coil pack is called a boot. 

 

[Wigpro]

Any bad coil packs should throw an error code so I would not do anything until I got the codes read....

Ford V-10s have a tendency to blow out spark plugs - so before you go pulling plugs make sure you understand how to do it properly.

I would also check the fuel pressure and the fuel pressure regulator.

Good Luck,

Jim

 

[OLDRACER]

Wow, last time I posted that my v10 of that era blew out a spark plug (probably 10 years ago) on a forum I was jumped on as everything from a fool to a liar. That is why I made such a gentle suggestion. Must be things have changed.

 

[jyro]

That's a fubar from Ford. It's common place today for all those type plugs. That's why I wouldn't even touch a plug with 25,000 miles on it unless it was carbon tracked on the porcelain. We are a older gentler bunch today.  on a side note, at 25000 highway miles it shouldn't have much buildup.

 

[(Chip)]

Bad coil packs usually don't throw a code.

 

[kratedisease]

NO check engine light, and I am looking for the connector for the code reader under the dash.... cannot find it... believe it or not !!