Have you only had one opinion about whats wrong? Never go with just one, seems that half of diagnostics if Florida seems to be opinion and guesstimation. This is an example I've got to share cause this little shit gave me alot of lip about how I had wronged him, he didnt have to pay, he was going to call his lawyer(I always tell them the public defender doesnt do civil cases), etc. I had a customer wanted me to reposses his 91 saturn because it wouldnt run. He didnt know why it wouldnt run, just stated that it wouldnt run and he "couldnt keep putting money into it" (people usually say this the first time their 10 year old car they bought 6 months ago has a problem). I convinced him that it would be in his best interest to have it checked out by a mechanic. The first one he took it to said it had a blown motor. So he towed it back to his apartment and called me to come pick it up/reposses it. It took about an hour for me to do a compressions test, ignition test, then test the fuel system and find the fuel wasn't pumping. It cost me $80 for a pump and $10 for a filter. I charged him $225. ( $80 cost on the pump installed in the tank,$10 cost on the filter, towed it from his apartment, tightened the cam bearings( some reason the previous mech had loosened all of the cam bearings on both cam's), put on the valve cover, reinstalled all the crap the previous mech had disconnected, etc.) Called the customer and told him to pick up his car. Bottom line of my rant (please forgive me, its fricken stressful) is.....Even if it was diagnosed by an expert go find another expert opinion just to be safe.