diagnose this

On Wed, 7 Apr 2010 11:12:22 -0700 (PDT), N8N >
wrote:

>On Apr 7, 1:30*am, Ashton Crusher > 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
>>
>> Problem solved.
>>
>> Shop didn't like the Motorcraft double platinum plugs that were in it,
>> said it shouldn't be using platinum plugs. *Told them the plugs only
>> had 8K on them. *They couldn't find anything specific with their "test
>> equipment" so they recommended an injector cleaning. *Told them to go
>> ahead. *Very slight improvement but still not running right. *Shop
>> said they were 98% sure new non-plat plugs would fix it. * Told them
>> to go ahead. *It fixed it. *Now it runs fine. *Very strange. *I've
>> used motorcraft plat plugs for 137,000 miles with no problems till
>> now.- Hide quoted text -
>>
>> - Show quoted text -
>
>some engines just don't like platinums, especially older engines that
>may have a little blowby. They tend to foul and never burn clean. I
>hear of this most often with Bosch FWIW.
>
>nate


I've heard that about the bosch. But I looked at these plugs
(Motorcraft) before I took the truck in and they were clean, the
"center" plugs were "too clean" you might say, the porcelain on them
was as white as a new plug. The only thing I can think is that those
cylinders were running a little lean and the plugs were getting a
little too hot and the deposits on them turned to a white glaze that
was shorting out the spark. Probably new platinum plugs would have
fixed it too. However, you'd think that would have shown up on their
test equipment and they claim they didn't see anything that looked bad
with the plugs or wires.

On 4/8/2010 2:23 AM, Ashton Crusher wrote:
> On Wed, 7 Apr 2010 11:12:22 -0700 (PDT), >
> wrote:
>
>> On Apr 7, 1:30 am, Ashton > wrote:
>>> On Sat, 20 Mar 2010 01:58:58 -0700, Ashton >
>>> 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
>>>
>>> Problem solved.
>>>
>>> Shop didn't like the Motorcraft double platinum plugs that were in it,
>>> said it shouldn't be using platinum plugs. Told them the plugs only
>>> had 8K on them. They couldn't find anything specific with their "test
>>> equipment" so they recommended an injector cleaning. Told them to go
>>> ahead. Very slight improvement but still not running right. Shop
>>> said they were 98% sure new non-plat plugs would fix it. Told them
>>> to go ahead. It fixed it. Now it runs fine. Very strange. I've
>>> used motorcraft plat plugs for 137,000 miles with no problems till
>>> now.- Hide quoted text -
>>>
>>> - Show quoted text -
>>
>> some engines just don't like platinums, especially older engines that
>> may have a little blowby. They tend to foul and never burn clean. I
>> hear of this most often with Bosch FWIW.
>>
>> nate
>
>
> I've heard that about the bosch. But I looked at these plugs
> (Motorcraft) before I took the truck in and they were clean, the
> "center" plugs were "too clean" you might say, the porcelain on them
> was as white as a new plug. The only thing I can think is that those
> cylinders were running a little lean and the plugs were getting a
> little too hot and the deposits on them turned to a white glaze that
> was shorting out the spark. Probably new platinum plugs would have
> fixed it too. However, you'd think that would have shown up on their
> test equipment and they claim they didn't see anything that looked bad
> with the plugs or wires.

When I see Motorcraft I think original. Were these the original plugs
from the factory? The original plugs should be opposite plats. Two
different part numbers.

On Thu, 08 Apr 2010 07:19:16 -0400, Steve Austin
> wrote:

>On 4/8/2010 2:23 AM, Ashton Crusher wrote:
>> On Wed, 7 Apr 2010 11:12:22 -0700 (PDT), >
>> wrote:
>>
>>> On Apr 7, 1:30 am, Ashton > wrote:
>>>> On Sat, 20 Mar 2010 01:58:58 -0700, Ashton >
>>>> 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
>>>>
>>>> Problem solved.
>>>>
>>>> Shop didn't like the Motorcraft double platinum plugs that were in it,
>>>> said it shouldn't be using platinum plugs. Told them the plugs only
>>>> had 8K on them. They couldn't find anything specific with their "test
>>>> equipment" so they recommended an injector cleaning. Told them to go
>>>> ahead. Very slight improvement but still not running right. Shop
>>>> said they were 98% sure new non-plat plugs would fix it. Told them
>>>> to go ahead. It fixed it. Now it runs fine. Very strange. I've
>>>> used motorcraft plat plugs for 137,000 miles with no problems till
>>>> now.- Hide quoted text -
>>>>
>>>> - Show quoted text -
>>>
>>> some engines just don't like platinums, especially older engines that
>>> may have a little blowby. They tend to foul and never burn clean. I
>>> hear of this most often with Bosch FWIW.
>>>
>>> nate
>>
>>
>> I've heard that about the bosch. But I looked at these plugs
>> (Motorcraft) before I took the truck in and they were clean, the
>> "center" plugs were "too clean" you might say, the porcelain on them
>> was as white as a new plug. The only thing I can think is that those
>> cylinders were running a little lean and the plugs were getting a
>> little too hot and the deposits on them turned to a white glaze that
>> was shorting out the spark. Probably new platinum plugs would have
>> fixed it too. However, you'd think that would have shown up on their
>> test equipment and they claim they didn't see anything that looked bad
>> with the plugs or wires.
>
>When I see Motorcraft I think original. Were these the original plugs
>from the factory? The original plugs should be opposite plats. Two
>different part numbers.

They are whatever is sold retail, maybe it's Autolite or something,
whatever the "ford" brand is. They are double plats, you can't get
the original single special side for the left and right that they put
in at the factory.

What an odd assumption... the vehicle in question is nearly 20 years old...

As far as misfiring plugs showing up on anyones "test equipment" - nobody
uses an ignition analyzer type scope these days... (disclaimer - Ford
supplies us ignition test leads with the current VMM testing module - but
techs are seldom directed to use the feature when reading the PC/ED).
Occasionally we are directed to perform a coil "stress test". Setting up and
performing the test costs more than simply replacing the coil as a
diagnostic test step...

The new 6.2 gas engine may offer some interesting symptoms with it's dual
plug arrangement.


"Steve Austin" > wrote in message
. ..
> On 4/8/2010 2:23 AM, Ashton Crusher wrote:
>> On Wed, 7 Apr 2010 11:12:22 -0700 (PDT), >
>> wrote:
>>
>>> On Apr 7, 1:30 am, Ashton > wrote:
>>>> On Sat, 20 Mar 2010 01:58:58 -0700, Ashton >
>>>> 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
>>>>
>>>> Problem solved.
>>>>
>>>> Shop didn't like the Motorcraft double platinum plugs that were in it,
>>>> said it shouldn't be using platinum plugs. Told them the plugs only
>>>> had 8K on them. They couldn't find anything specific with their "test
>>>> equipment" so they recommended an injector cleaning. Told them to go
>>>> ahead. Very slight improvement but still not running right. Shop
>>>> said they were 98% sure new non-plat plugs would fix it. Told them
>>>> to go ahead. It fixed it. Now it runs fine. Very strange. I've
>>>> used motorcraft plat plugs for 137,000 miles with no problems till
>>>> now.- Hide quoted text -
>>>>
>>>> - Show quoted text -
>>>
>>> some engines just don't like platinums, especially older engines that
>>> may have a little blowby. They tend to foul and never burn clean. I
>>> hear of this most often with Bosch FWIW.
>>>
>>> nate
>>
>>
>> I've heard that about the bosch. But I looked at these plugs
>> (Motorcraft) before I took the truck in and they were clean, the
>> "center" plugs were "too clean" you might say, the porcelain on them
>> was as white as a new plug. The only thing I can think is that those
>> cylinders were running a little lean and the plugs were getting a
>> little too hot and the deposits on them turned to a white glaze that
>> was shorting out the spark. Probably new platinum plugs would have
>> fixed it too. However, you'd think that would have shown up on their
>> test equipment and they claim they didn't see anything that looked bad
>> with the plugs or wires.
>
> When I see Motorcraft I think original. Were these the original plugs
> from the factory? The original plugs should be opposite plats. Two
> different part numbers.

On 4/10/2010 9:53 AM, Jim Warman wrote:
> What an odd assumption... the vehicle in question is nearly 20 years old...
>


It only has 130k on it. I see factory plugs at that kind of mileage
frequently.