Medical Malpractice mis diagnosis

[tlcthis]

I have had my 1999 Pontiac Montana serviced at the same garage. On 03/27/06 had a intake manifold gasket replaced (had extended warranty to cover it). On 04/21/08 had it in stated thought oil was getting in the coolant. They said "No evidence of coolant and oil mixing" My husband flushed the coolant system on 4/23/08. On 4/25/08 the check engine light came on and then started to flash. I got it to a chevy garage and they are saying I need a head gasket. I would like to know if I have a legal case against the original garage for not properly diagnosing a problem. I still have the coolant my husband flushed out and could have it for analyzed.

 

[tlcthis]

Sorry forgot to mention I am in PA