i put a boost guage on my 7 and found out i was only putting down 3 psi of boost. found out that the coupling connecting the y pipe to the intercooler was ripped. so i fixed that took her for a drive, she boosted till 8 psi, ran out of road so i stopped, turned around and i hear a clunk noise and the motor will not start up now. the motor has about 140,000 kms on it.
do you guys think the motor is pooched? could it be something else? i don't have a compression tester so i cannot check that. Also if it blew up, why would it have happened? aren't they good for 10 psi? also i never revved past 5 k

 

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No way to tell what happend from the info provided. You need to get a compression test done. Go to autozone and buy a compression tester, just remove the valve so it doesnt peak hold.

 

Write your info and your past symptoms before your boost gauge and after.