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Discussion Starter · #1 ·
Sigh, here we go again :( Just got a 95 LS fixed, thanks to some great help in another thread. Replaced distributor, one problem solved, but along comes another. Car is misfiring, discovered fresh oil on the #6 spark plug. Also, there is alot of smoke (steam) coming out of the pipe while running. A logical guess would surmise that this is not good news.

My question is: What would be the most likely/common cause of this problem in these V6s? A blown head gasket comes to mind, but what about the oil on the #6 plug? Would a blown head gasket cause this as well, or is there a much more serious ($$$) problem? Cracked/warped head? Poor ring seating in that one cylinder? Thanks again for any advice.


Mike
 

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oil is on the plug wire and the part of the plug that is outside of the head right? if so thats a valve cover gasket. that could cause the plug to foul im not sure about this part but i think it could possibly cause smoking.

thats not near as bad as replacing the head gaskets like im doing right now @- i havent priced new vcg so idk how much they are yet..... also im not sure about this but you might be able to over tighten the bolt that is right next to that spark plug hole without removing the IM. its possible that that may stop the leak. however if you break the bolt its not my fault ;) if removing the IM is required replace the vcg dont just tighten the bolt, youll probally end up kicking yourself when you have to take it appart again in a coule months to do it right. its possible that overtightening the bolt would make the leak stop(im not even sure about that) but i am by no means recomending that you tighten the bolt anymore
 

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ah super, :rolleyes: , the infamous cylander #6......

at least ur rod didnt go.... oil inside the combustion chamber (enough to be seen on a pulled plug) could be from a head gasket, cracked head or piston, or possibly a piston ring. i doubt valve seels would let enough oil in for it to be seen on a spark plug. all are high dollar repairs. if you take it to a shop they'd probally recomend a new engine.......

get a compression check.... also is there any oil in your radiator fluid? that would say most likely head gasket or head damage. is is possible that the oil isnt from inside the cylander?(u touched it against something and it got oilly)

im in the process of doing my head gaskets, its not as hard a job as i thought it was going to be..... i havent started reassembly yet though, that will be very tedious.
 

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Discussion Starter · #5 ·
I figured that this repair wasn't going to be cheap :(. What I was really wanting to know is if there is a certain component in these V6s that have problems. Do 2nd gen V6s commonly warp or crack heads? Are blown head gaskets another common problem? Would a blown head gasket on these engines cause a plug to be fouled out with oil?

This car has only 104K miles on the clock. It would seem that a cracked piston or poor ring sealing should be the least likely culprit in light of the mileage.

My friend was planning to do a compression check, but I've not talked to him yet to hear the results.
 

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blown gaskets and warped cracked heads are common on just about any car...except these economic fuel effeicent double emission stantard pieces of crap 03s+...:p if your car is OLD and has lots of MILES, your car is vulnerable to crack/warped heads and blown gaskets..the list goes on and there all high dallor.

Tip 1. when your car starts to over heat (doesnt steam, but just gets to the red on the gauge) shut the car off and let it sit. Over heating your car leads to warping the head, and cracking also.
It doesnt matter when, where, why or how its over heating just shut if off. (not saying you over heated the car, this is just a cause for the cracked/warped head)

As for gaskets, the cars old, and probaly has alot a miles on it, maybe it had poor maitnence? or was driven hard alot? anywase its like doing heart surgery on a engine. and most people rather trash the engine then repair it, and its usually easier that way because the heads are either cracked or warped..

i forget how to test the exhaust...but i think its if its black its oil, blue its coolant..and white is good. MAYBE. you can also smell it.

check your oil. i swear everyone is gettin water in the oil. (my moms car went to hell, water in the oil) (my dads trucker's truck went to hell, water in the oil)
 

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the only somewhat common engine problem with mx6s is oil starvation for the rod bearings on cyl#6. that doesnt sound like your problem. head gaskets arent that common a failure on mx6 engines. a blown headgasket however could cause a fouled plug. or it my case, 3 fouled plugs, and believe it or not the engine still ran.
 
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Discussion Starter · #8 ·
Aussomea said:
the only somewhat common engine problem with mx6s is oil starvation for the rod bearings on cyl#6. that doesnt sound like your problem. head gaskets arent that common a failure on mx6 engines. a blown headgasket however could cause a fouled plug. or it my case, 3 fouled plugs, and believe it or not the engine still ran.

Thanks man, that's pretty much what I was wanting to know. Among the hundereds of 2nd gen owners on this site, I figured there would have to be a pattern of known common failures among a certain percentage of the cars. Looks like the problem I'm dealing with is uncommon :( Thanks again for your help.
 
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After you get the heads off take them to a good mechine shop have them checked for cracks (pressure checked) If they are cracked to check, repair, valve job around $350.00>$500.00 then a gasket set $370.00 Timing belt and other little things it adds up fast. You might want to get with Hughes in the parts for sale part of forum [email protected] I just got an engine from him. He had an engine with around 72K I think for $500.00+ shipping.
Cheers George
 

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Discussion Starter · #10 ·
Update: My friend finally started digging into the motor to find the source of the problem. He found a camshaft that was broke in half. Needless to say, we didn't expect that :( Any ideas about where to get a cam?

George, thanks for the engine link. We may need it...
 

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i just got one from silverpgt-r on PT heres a link http://www.probetalk.com/forums/showthread.php?s=&threadid=1701067971 his IM is snowbrder9999 if u want to talk to him. the item was shipped next day id definitely recomend him. i think hes still got all the cams except the one i bought.

if u dont buy from him, id recomend hughes46 in mx6.com's forsale section. he's got 20 mx6's and has done business with half(exaduration) the people on this site :tup:
 

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Discussion Starter · #12 ·
Aussomea said:
if u dont buy from him, id recomend hughes46 in mx6.com's forsale section. he's got 20 mx6's and has done business with half(exaduration) the people on this site :tup:
Thanks for the tip. Another member (mts3, aka Tyson Sherman) also recommended hughes46, so he must be the man to talk to :) I will be contacting him.
 

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Discussion Starter · #13 · (Edited)
Aussomea said:
the only somewhat common engine problem with mx6s is oil starvation for the rod bearings on cyl#6.

How about oil starvation of the cam bearing above the #6 cylinder?

Here are some pics:

http://photos.groups.yahoo.com/grou....jpg?bcpeJyuBXeUaHhxf&.cx=150&.cy=112&.type=u

Is it possible to repair the damage at the cam bearing area, or is it necessary to buy a new head? I was hoping a machine shop could grind that area out and insert some sort of a cap or bearing.
Thanks.
 
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