Blown motor?

[94greentsi]

Hey guys. Any help here would be appreciated. I was heading up on a road trip in my talon, and I noticed that as I was cruising at 140km/hr, my boost guage bounced on the max line twice. I immediately slowed down and babied the car until I reached the next town. BTW I have a stock boost guage, which I know is not very accurate. I have no modifications to the motor, turbo, or boost pressure. I didnt notice a problem with the car until I began to slow down, and the revs came down. It is best described as a feeling like the tires were seperating, when in actuality something was seriously wrong with the motor. The motor felt like it was extremely unbalanced at low RPM's and it had very low power. It idled fine at 750 like its supposed to, but I knew it wasnt running on all 4 slugs.

I rolled it into the local auto repair shop where the mechanic did a check of the spark plugs. The #2 spark plug was completely coverd in oil deposits that had baked on. All of the other plugs were fine. He did a compression check on that cylinder, and it was at 0!!

Blown piston? Rings? I dont know why a completely stock motor would do this, but the motor has been freshly rebuilt by the previous owner about 8000km ago. I am not sure if it was built wrong, or if I wrecked the motor somehow. Did the turbo put too much boost into the motor? I thought it was strange how the boost guage bounced off the max point 2 times.

Any help would be greatly appreciated. I have to get the motor rebuilt this week.

Thanks

forever

 

[timloomis]

sounds like a valve problem or a blown headgasket.either way,your gonn have to pull the head.even fried rings will give some pressure.

 

[TUI2I30]

do a leak down test according to this site. http://www.dsmgrrrl.com/FAQs/leakdown.htm I found my blown rings on the #2 cylinder this way. This will help you determine what is causing your compression loss. Do this before your head is pulled so you are not guessing later. It is also possible that when they rebuilt the motor they did not replace the auto-tensioner on the timing belt which could have allowed your timing belt to skip. Causing a bent valve, which will show up on a leakdown test. As far as the stock boost gauge question, can't help you. I don't even look at that thing... ever... seriously!

 

[Defiant]

One of these:

 

[hereitcomes]

defiant that is sexy.

 

[psychlow]

One of these:

Commonly referred to textually as a "burnt valve".

 

[Eagle_of_Fire]

How much does and engine rebuild usuall cost.. say i have a burnt ring or a burnt up valve.