996 engine failure

[BlackC2]

My mechanic thinks someone put something in my gas that made my piston crack. What could do that?

[Loren]

Sorry, not enough information here.

Fault codes?

What is the failure analysis based on? engine dis-assembly?

[BlackC2]

No codes. Just ran rough and died. I restarted it it smoked a lot sand raw oil was coming out onne pipe

[logray]

Wow, that would be some really bad gas. Perhaps someone poured cement or paint into the tank. Do you have any enemies?

Or perhaps a really bad intake leak and a lot of material going in the intake manifold and wreaking havoc upon the cylinders/pistons/rings (perhaps intake was not attached properly?) .

Agree with Loren though, without complete dis-assembly/pics/codes it's tough to say for certain.

[BlackC2]

The only thing done so far, was the three right side spark plugs were removed and one of the prongs on the #5 spark plug was bent. Coolant in oil too. Immediately I was told I need a new motor. I had my car towed to my guy and he's out for a couple weeks.

Edited August 14, 2011 by BlackC2

[rb101]

I think you had a cylinder wall failure in #5 and the piece was pounded around by the piston. Hopefully the engine has no other damages and can be sleeved.

[logray]

Sounds like it could be a slipped sleeve/ d-chunk failure or perhaps just an intermix in the head that led to further problems since it went by unaddressed.

"Previously unseen cylinder failure. It is a known fact that the casting plant that made the blocks for Porsche was unable to keep up with demand and also experienced casting problems, turned to a 3rd party with a freeze-cast MMC (metal matrix composite) liner which was cast into the block. Sleeve had a very small lip at the head end to keep it from moving. On this cylinder, the lip broke, allowing the sleeve to intrude into the crankcase, leading to a D-chunk failure coupled with a delamination of the cast in liner from the block."

From http://www.flat6innovations.com/engine-failures-illustrated

[BlackC2]

Thanks, but do you think sugar in my gas could cause this?

[Dharn55]

I think sugar in the gas causes fuel system problems not cracked cylinder/pistons etc. However if you could prove that it was malicious damage there might be a basis for a claim under your comprehensive insurance coverage. Just a thought.

Edited August 14, 2011 by Dharn55

[Loren]

The problem with this rumor is that it simply isn't true. As it turns out, sugar doesn't dissolve in gasoline. Pouring sand into the gas tank would have about the same effect as pouring in sugar. The sand or sugar might clog up the fuel filter, and that could disable the car, but it's not a sure thing.

[violaGT3]

My buddy burnt out a piston due to a failing injector. Not sure if it would crack the piston but then again at 3krpms I am not sure if anything wouldn't crack a rogue piston. Sad to hear it.

Edited August 14, 2011 by ViolaGT3

[BlackC2]

The problem with this rumor is that it simply isn't true. As it turns out, sugar doesn't dissolve in gasoline. Pouring sand into the gas tank would have about the same effect as pouring in sugar. The sand or sugar might clog up the fuel filter, and that could disable the car, but it's not a sure thing.

If I had to guess, I think it might have been orange juice or soda. Might that cause this problem?

[logray]

If you are suspecting something was put into the gas that clogged an injector, pull the injectors and have them bench tested. They will be able to tell if they are clogged/bad/etc. Although probably not be able to tell if there was something put into the gas - just assess the state of the injectors and clean/repair them if they are out of spec.

There is a service in Sacramento called Dr. Injector.