2003 engine knock

I have a problem with my 2003 LS. 84,000 miles. When the engine is
warmed to run condition, the enine has a very loud knock above 2100
RPM. I first thought it was the oil control valve for the VVT so I
bought a new one. The CEL ( 0012) stopped coming on, but still the
noise. I changed the VVT unit, did a complete belt, water pump and all
seals. NO change ! I understand that a PCM condition (and replacement
by Mazda) is in effect. I run 5W-30 syn. oil. Could this really be a
PCM problem ?

Jasper

On 6/28/2010 1:09 PM, jasper wrote:
> I have a problem with my 2003 LS. 84,000 miles. When the engine is
> warmed to run condition, the engine has a very loud knock above 2100
> RPM. I first thought it was the oil control valve for the VVT so I
> bought a new one. The CEL ( 0012) stopped coming on, but still the
> noise. I changed the VVT unit, did a complete belt, water pump and all
> seals. NO change ! I understand that a PCM condition (and replacement
> by Mazda) is in effect. I run 5W-30 syn. oil. Could this really be a
> PCM problem ?
>
> Jasper

The first problem is to determine where the noise is coming from.
Head area or lower block area. A mechanics stethoscope may be of help.

An actual oil pressure reading (Not fun to do) may also be of some
limited help. I have a 99, and have used full synthetic oil (10W30) for
years. The mileage is about 89,000, and the engine has been turbo'd for
about 60,000. Minimal oil usage, and due to the turbo, oil changes are
usually frequent.

On Jun 28, 1:21*pm, Chuck > wrote:
> On 6/28/2010 1:09 PM, jasper wrote:
>
> > I have a problem with my 2003 LS. 84,000 miles. When the engine is
> > warmed to run condition, the engine has a very loud knock above 2100
> > RPM. I first thought it was the oil control valve for the VVT so I
> > bought a new one. The CEL ( 0012) stopped coming on, but still the
> > noise. I changed the VVT unit, did a complete belt, water pump and all
> > seals. NO change ! I understand that a PCM condition (and replacement
> > by Mazda) is in effect. I run 5W-30 syn. oil. Could this really be a
> > PCM problem ?
>
> > Jasper
>
> The first problem is to determine where the noise is coming from.
> Head area or lower block area. A mechanics stethoscope may be of help.
>
> An actual oil pressure reading (Not fun to do) may also be of some
> limited help. *I have a 99, and have used full synthetic oil (10W30) for
> years. The mileage is about 89,000, and the engine has been turbo'd for
> about 60,000. Minimal oil usage, and due to the turbo, oil changes are
> usually frequent.

Well, the noise sounds like the VVT area ( with a stethoscope ) and I
was using 10W-30 dino oil but switched to see if it would change
anything. Scoping anyplace else is not loud. I do have a real oil
pressure gauage in the engine compartment. 75 lb on start up. about 25
lb at hot idle. At 2000 RPM, 30lb +. If I drive around under 2000 RPM
all warmed up, no noise! If I add a little power or load the engine on
a hill, the noise goes away until the power unloads. Kind'a like a
"rod knock". If it were a connecting rod, it would have come out thru
the block by now! (over a year now) and I have turned it 7,000 + for
a time and nothing changes and the loise keeps up with ith RPM and no
louder. I have removed the other belts and no change.

Jasper

VVT Noise
The VVT rotating assembly on the end of the cam may be the culprit.
Seems that there is a pin assembly that can cause noise. (Service
Bulletin, etc.) I'd attach a picture, but my news server is not
accepting attachments for this group.



On 6/28/2010 10:33 PM, jasper wrote:

On Jul 1, 10:28*am, Chuck > wrote:
> VVT Noise
> The VVT rotating assembly on the end of the cam may be the culprit.
> Seems that there is a pin assembly that can cause noise. (Service
> Bulletin, etc.) I'd attach a picture, but my news server is not
> accepting attachments for this group.
>
> On 6/28/2010 10:33 PM, jasper wrote:

Yes, that assy. is controled by the PCM. The "control valve' and the
complete VVT assy. have been replaced. All of the "O" rings on the
control valve assy have been replaced, all belts, water pump, timming
belt and all the seals, idler and tensioner were replaced, injectors
cleaned, cyl. and intake system cleaned. The little screen that is in
the top of the control valve assy. has been replaced ! I am about
ready to jack up the hood and replace everything under it !!!!! Today
I took it to a Mazda Dealer and they said all they could do is pull
the engine apart until they found the problem ! CRAP ! I can do
that !!! I just want to know what the F*** is wrong !!!, so I can fix
it .

Jasper

On 7/1/2010 3:16 PM, jasper wrote:
> On Jul 1, 10:28 am, > wrote:
>> VVT Noise
>> The VVT rotating assembly on the end of the cam may be the culprit.
>> Seems that there is a pin assembly that can cause noise. (Service
>> Bulletin, etc.) I'd attach a picture, but my news server is not
>> accepting attachments for this group.
>>
>> On 6/28/2010 10:33 PM, jasper wrote:
>
> Yes, that assy. is controled by the PCM. The "control valve' and the
> complete VVT assy. have been replaced. All of the "O" rings on the
> control valve assy have been replaced, all belts, water pump, timming
> belt and all the seals, idler and tensioner were replaced, injectors
> cleaned, cyl. and intake system cleaned. The little screen that is in
> the top of the control valve assy. has been replaced ! I am about
> ready to jack up the hood and replace everything under it !!!!! Today
> I took it to a Mazda Dealer and they said all they could do is pull
> the engine apart until they found the problem ! CRAP ! I can do
> that !!! I just want to know what the F*** is wrong !!!, so I can fix
> it .
>
> Jasper
Sounds to me that you will need to really determine exactly where the
noise is the strongest. On an engine without plug wells, I'd pull the
valve cover and run the engine. Not so easy to do on a Miata. Not having
a VVT, I don't know what the Gotchas might be.

So the dealer hasn't a clue either. That's not too unusual, since
dealers usually replace engines rather than repair them.

On Jul 2, 2:09*am, Chuck > wrote:
> On 7/1/2010 3:16 PM, jasper wrote:
>
>
>
> > On Jul 1, 10:28 am, > *wrote:
> >> VVT Noise
> >> The VVT rotating assembly on the end of the cam may be the culprit.
> >> Seems that there is a pin assembly that can cause noise. (Service
> >> Bulletin, etc.) I'd attach a picture, but my news server is not
> >> accepting attachments for this group.
>
> >> On 6/28/2010 10:33 PM, jasper wrote:
>
> > Yes, that assy. is controled by the PCM. The "control valve' and the
> > complete VVT assy. have been replaced. All of the "O" rings on the
> > control valve assy have been replaced, all belts, water pump, timming
> > belt and all the seals, idler and tensioner were replaced, injectors
> > cleaned, cyl. and intake system cleaned. *The little screen that is in
> > the top of the control valve assy. has been replaced ! I am about
> > ready to jack up the hood and replace everything under it !!!!! *Today
> > I took it to a Mazda Dealer and they said all they could do is pull
> > the engine apart until they found the problem ! CRAP ! I can do
> > that !!! I just want to know what the F*** is wrong !!!, so I can fix
> > it .
>
> > Jasper
>
> Sounds to me that you will need to really determine exactly where the
> noise is the strongest. On an engine without plug wells, I'd pull the
> valve cover and run the engine. Not so easy to do on a Miata. Not having
> a VVT, I don't know what the Gotchas might be.
>
> So the dealer hasn't a clue either. That's not too unusual, since
> dealers usually replace engines rather than repair them.- Hide quoted text -
>
> - Show quoted text -

Well I took the car in and had Mazda do a complete check on the
engine. $56.29. OK price for me. PCM is good and has the latest
updates. The noise is from the inside of the engine. Rod bearing or
broken piston. Eather way, it looks like I will need a new short
block. I'm just getting too old for this kind of crap. It is easier to
pull the engine and drop the pan to check the rods and pistons. I have
all the things to do it, just too old and with handycaps. If it is a
rod, it will mean a crank and a piston will need a bore job and
pistons + rings. Used short block is easier. Not too expensive,
cheaper than a rework.

Jasper