diagnose this

On Sun, 21 Mar 2010 05:47:20 GMT, "Jim Warman"
> wrote:

>Cap and rotor? Are you familiar with this engine?
>

I thought my "(OK, I hope this engine does have a cap/rotor!)"
disclaimer was enough to say that it was general advice. I deeply and
humbly appologize if I caused you distress, but I've seen the problem
I described before and figured it was a good guess.

>
>"PeterD" > wrote in message
.. .
>> On Sat, 20 Mar 2010 01:58:58 -0700, Ashton Crusher >
>> wrote:
>>
>>>92 Ford Explorer 4.0L OHV V6 130K miles, 10K on double plat plugs,
>>>nearly new plug wires. O2 sensor was replaced about 40K ago
>>>
>>>Sometimes Runs rough when first started. Not just first start of the
>>>day, but even when warmed up and then shut down for 15 minutes it will
>>>often run rough initially like one cylinder is missing.
>>>
>>>Roughness usually goes away after it's warmed up but lately it's
>>>started to have a bucking/missing/popping under light acceleration.
>>>Giving it more gas usually smooth's it out. It will run on up to
>>>redline and shift into the next gear and has no problem running up to
>>>90 mph. So unlike what I think of as the typical 'worn out plug"
>>>misfire that shows up at high rpm and high load, this show up at
>>>medium rpm light to medium load.
>>>
>>>It has not turned on the check engine light
>>>
>>>Any ideas?
>>>
>>>Things I'm thinking it might be..
>>>
>>>water in gas
>>>bad gas
>>>bad injector(s)
>>>bad coil
>>
>> You've replaced the cap/rotor? One real possibility is moisture in/on
>> the cap/rotor causing a mis-fire, when the engine warms the moisture
>> evaporates, then re-condenses when the engine cools.
>>
>> (OK, I hope this engine does have a cap/rotor!)
>

Oh, don't get your hopes up.... you haven't caused any distress but you have
been a source of amusement.... One of the big problems we see stems from not
knowing what we are speaking of...

I don't tell people how to fix their Dolby 5.1 surround sound systems
because I'm not familiar with them.... I don't tell them how to cure
diarrhea because I'm not a doctor and I'm not familiar with the concern...

Silly wild ass guesses are silly wild ass guesses - while they might make
you feel better, they do little for anyone else that is unfamiliar with
their system...


"PeterD" > wrote in message
...
> On Sun, 21 Mar 2010 05:47:20 GMT, "Jim Warman"
> > wrote:
>
>>Cap and rotor? Are you familiar with this engine?
>>
>
> I thought my "(OK, I hope this engine does have a cap/rotor!)"
> disclaimer was enough to say that it was general advice. I deeply and
> humbly appologize if I caused you distress, but I've seen the problem
> I described before and figured it was a good guess.
>
>>
>>"PeterD" > wrote in message
. ..
>>> On Sat, 20 Mar 2010 01:58:58 -0700, Ashton Crusher >
>>> wrote:
>>>
>>>>92 Ford Explorer 4.0L OHV V6 130K miles, 10K on double plat plugs,
>>>>nearly new plug wires. O2 sensor was replaced about 40K ago
>>>>
>>>>Sometimes Runs rough when first started. Not just first start of the
>>>>day, but even when warmed up and then shut down for 15 minutes it will
>>>>often run rough initially like one cylinder is missing.
>>>>
>>>>Roughness usually goes away after it's warmed up but lately it's
>>>>started to have a bucking/missing/popping under light acceleration.
>>>>Giving it more gas usually smooth's it out. It will run on up to
>>>>redline and shift into the next gear and has no problem running up to
>>>>90 mph. So unlike what I think of as the typical 'worn out plug"
>>>>misfire that shows up at high rpm and high load, this show up at
>>>>medium rpm light to medium load.
>>>>
>>>>It has not turned on the check engine light
>>>>
>>>>Any ideas?
>>>>
>>>>Things I'm thinking it might be..
>>>>
>>>>water in gas
>>>>bad gas
>>>>bad injector(s)
>>>>bad coil
>>>
>>> You've replaced the cap/rotor? One real possibility is moisture in/on
>>> the cap/rotor causing a mis-fire, when the engine warms the moisture
>>> evaporates, then re-condenses when the engine cools.
>>>
>>> (OK, I hope this engine does have a cap/rotor!)
>>

Nothing that turns on the check engine light. Guess I'll have to run
it down to autozone and see if there are any hidden codes their
scanner turns up. Never uses oil. I'll check the plugs.


On Sun, 21 Mar 2010 05:50:43 GMT, "Jim Warman"
> wrote:

>Codes? Is it using more oil than normal? Check plugs #2 and #5
>
>
>"Ashton Crusher" > wrote in message
.. .
>> 92 Ford Explorer 4.0L OHV V6 130K miles, 10K on double plat plugs,
>> nearly new plug wires. O2 sensor was replaced about 40K ago
>>
>> Sometimes Runs rough when first started. Not just first start of the
>> day, but even when warmed up and then shut down for 15 minutes it will
>> often run rough initially like one cylinder is missing.
>>
>> Roughness usually goes away after it's warmed up but lately it's
>> started to have a bucking/missing/popping under light acceleration.
>> Giving it more gas usually smooth's it out. It will run on up to
>> redline and shift into the next gear and has no problem running up to
>> 90 mph. So unlike what I think of as the typical 'worn out plug"
>> misfire that shows up at high rpm and high load, this show up at
>> medium rpm light to medium load.
>>
>> It has not turned on the check engine light
>>
>> Any ideas?
>>
>> Things I'm thinking it might be..
>>
>> water in gas
>> bad gas
>> bad injector(s)
>> bad coil
>

On Sat, 20 Mar 2010 09:03:50 -0400, PeterD > wrote:

>On Sat, 20 Mar 2010 01:58:58 -0700, Ashton Crusher >
>wrote:
>
>>92 Ford Explorer 4.0L OHV V6 130K miles, 10K on double plat plugs,
>>nearly new plug wires. O2 sensor was replaced about 40K ago
>>
>>Sometimes Runs rough when first started. Not just first start of the
>>day, but even when warmed up and then shut down for 15 minutes it will
>>often run rough initially like one cylinder is missing.
>>
>>Roughness usually goes away after it's warmed up but lately it's
>>started to have a bucking/missing/popping under light acceleration.
>>Giving it more gas usually smooth's it out. It will run on up to
>>redline and shift into the next gear and has no problem running up to
>>90 mph. So unlike what I think of as the typical 'worn out plug"
>>misfire that shows up at high rpm and high load, this show up at
>>medium rpm light to medium load.
>>
>>It has not turned on the check engine light
>>
>>Any ideas?
>>
>>Things I'm thinking it might be..
>>
>>water in gas
>>bad gas
>>bad injector(s)
>>bad coil
>
>You've replaced the cap/rotor? One real possibility is moisture in/on
>the cap/rotor causing a mis-fire, when the engine warms the moisture
>evaporates, then re-condenses when the engine cools.
>
>(OK, I hope this engine does have a cap/rotor!)


It's a good thought but it is distributorless. It could be that the
wires aren't very good I suppose, they are new Bosch and I've never
had trouble with Bosch before but there's always a first time.

On Sat, 20 Mar 2010 06:12:04 -0700 (PDT), willy
> wrote:

>On Mar 20, 9:03*am, PeterD > wrote:
>
>> You've replaced the cap/rotor? One real possibility is moisture in/on
>> the cap/rotor causing a mis-fire, when the engine warms the moisture
>> evaporates, then re-condenses when the engine cools.
>>
>> (OK, I hope this engine does have a cap/rotor!)- Hide quoted text -
>>
>> - Show quoted text -
>
>It isn't, "the moisture evaporates, then re-condenses when the engine
>cools."
>
>These are noted for vacumm leaks at the plentum, blown head gaskets
>and fuel pressure problems. All of which will cause your symptoms. You
>need to diagnosis it, instead of guessing.
>


I am trying to diagnose it by starting with some educated thoughts.

On Sun, 21 Mar 2010 05:50:43 GMT, "Jim Warman"
> wrote:

>Codes? Is it using more oil than normal? Check plugs #2 and #5
>
>
>"Ashton Crusher" > wrote in message
.. .
>> 92 Ford Explorer 4.0L OHV V6 130K miles, 10K on double plat plugs,
>> nearly new plug wires. O2 sensor was replaced about 40K ago
>>
>> Sometimes Runs rough when first started. Not just first start of the
>> day, but even when warmed up and then shut down for 15 minutes it will
>> often run rough initially like one cylinder is missing.
>>
>> Roughness usually goes away after it's warmed up but lately it's
>> started to have a bucking/missing/popping under light acceleration.
>> Giving it more gas usually smooth's it out. It will run on up to
>> redline and shift into the next gear and has no problem running up to
>> 90 mph. So unlike what I think of as the typical 'worn out plug"
>> misfire that shows up at high rpm and high load, this show up at
>> medium rpm light to medium load.
>>
>> It has not turned on the check engine light
>>
>> Any ideas?
>>
>> Things I'm thinking it might be..
>>
>> water in gas
>> bad gas
>> bad injector(s)
>> bad coil
>

A couple people have suggested fuel pressure regulator. For some
reason it's been getting somewhat BETTER gas mileage lately, which
perhaps is a symptom of low fuel pressure? And the popping, missing
perhaps is also a symptom of low fuel pressure? My fuel pressure
tester is loaned out so I will have to get it back and take a look.

On Sun, 21 Mar 2010 15:23:21 -0700, Ashton Crusher >
wrote:

>
>A couple people have suggested fuel pressure regulator. For some
>reason it's been getting somewhat BETTER gas mileage lately, which
>perhaps is a symptom of low fuel pressure? And the popping, missing
>perhaps is also a symptom of low fuel pressure? My fuel pressure
>tester is loaned out so I will have to get it back and take a look.

Not sure, but a rich mixture should throw a code, probably through the
02.
No experience with Ford, but the only time I had that bucking on
acceleration new injectors fixed it. Rough idle in drive at a light
too.
That was a 2.8 in a Celebrity.
Think I had my mech replace all 6 of them, and it cost me about 5
bills. I'm a little hazy on it, but it fixed it for good and I drove
it until about 190k miles before rust ate it up.
Did the injectors at about 140k miles
I've tested injectors (Deltac II's I think) on a couple of my other
cars with an ohmmeter and always got readings all over the place, but
within the spec range.
The ones that came from the car that was running good (for example I
pulled the injectors on the cars I sent to the boneyard due to rust)
worked fine in the trouble car, though you couldn't tell from the ohm
readings.
Just a thought.

--Vic

CWLee > wrote:
>
>It took almost 2 years, and $1,400, of replacing/repairing
>one thing another until the "upper and lower intake manifold
>gaskets" were replaced. The mechanic tried that after
>allowing butane or propane to be released in various places
>as the cold engine was idling, and the fact that the engine
>speeded up when the butane/propane was released in a certain
>place suggested to him that there was a leak there, and that
>the leak was allowing the butane/propane to be sucked in and
>burned with the gasoline. His theory was that this leak was
>only there when the engine was cold, and that when it warmed
>up the metal expansion closed the leak; when the engine was
>cold, and the leak was there, additional air was being
>sucked in and diluting the gasoline/air mixture so much that
>the missing and stumbling was being caused.

This is the standard procedure for finding vacuum leaks of all sorts. And
if you encounter rough running problems that seem random, one of the first
things to do is to start looking for vacuum leaks.

>(What I'm reporting here is my experience, and what my
>mechanic told me. I have no automotive skills, and thus
>offer this only for consideration.)

It is an excellent offer, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"Ashton Crusher" > wrote in message
...
> 92 Ford Explorer 4.0L OHV V6 130K miles, 10K on double plat plugs,
> nearly new plug wires. O2 sensor was replaced about 40K ago
>
> Sometimes Runs rough when first started. Not just first start of the
> day, but even when warmed up and then shut down for 15 minutes it will
> often run rough initially like one cylinder is missing.
>
> Roughness usually goes away after it's warmed up but lately it's
> started to have a bucking/missing/popping under light acceleration.
> Giving it more gas usually smooth's it out. It will run on up to
> redline and shift into the next gear and has no problem running up to
> 90 mph.

There's your problem--you are going faster than what the speedometer goes up
to.

Vacuum leaks when cold a fairly common with most flavours of the 4.0
Explorer engine that feature the plastic upper manifold... Easiest way to
check for the concern is to smoke test the intake after a cold soak... this
type of concern generally doesn't have a coolant leak to accompany it.

The upper intake is sealed to the lower intake with six individual "o-rings"
.... any or all of these can leak.