hissing? First thing I'd look for is a vacuum leak.
okay. I'm not too smart on engines, but my buddy knows a little bit. He said he thinks it might be a blown head gasket. Could that be it?
Are you loosing coolant? Do you have low compression on one or more cylinders? If no then it's likely not the head gasket... Either way you need proper tools to diagnose it. Either take it somewhere or buy a compression tester and/or a vacuum tester and get started (vacuum leaks I generally stick my head under the hood at first and see if I can't figure out where the sound is coming from... sometimes you get lucky). On a side note... 9/10 buddies who "know about cars" will prescribe the shotgun method of fixing problems and cost you a small fortune in the process. If your buddy jumped to that conclusion without asking you the questions I just did then chances are he would be one of those 9... When in doubt take it to a trusted well recommended mechanic. Sad thing is about 7/10 mechanics will be the same way so you really have to find a decent mechanic especially when diagnosing something. Just about anyone can do a brake job, not all will be able to properly go about diagnosing a problem... So ask family/friends...
I'm not losing coolant. Its a 5 speed and with my foot to the floor it'll make it to 35mph in about 12mins. No horsepower what so ever. I mean my friend stuck his head under the hood and he knows alot about mustangs and is in college for motorsports engineering. Thanks for the help bro, I really appreciate it.
Adam4753 is right, most performance-related problems with VWs is due to a vaccuum leak. Just go and buy some vaccuum hose for like $3 and replace the two short pieces coming from the fuel pressure regulator located on the front of your engine, it is a cylendrical metal piece, one hose goes to the airbox and the other to the throttle body. Next, inspect the breather hose on the front of the engine. It is a hard plastic hose held in place my a metal clip. Take the clip off and inspect the end. I had a leak from there once, just replaced the hose and it was fine. Got one from the junk yard for like $10. New its like $50 but sometimes you get lucky at the junk yard and find one that hasnt been snapped off or taken already. If that doesnt fix it, it could be your ignition coil losing spark due to being cracked, yet another common problem with these. Hope that helps.
Make sure vehicle is not over heating if its not then your hed gasket is ok. second on vaccum leaks the eng runs rough at idle (stopped at light)and runs smooth at high speeds if thats ok then u have no vaccum leaks.whatit sounds like is it may have a plugged exhaust the hissing noise is the exhaust trying to escape plugged exhaust will cause car to not have any pwr and barely move at 10mph try to loosen exhaust beforecatalytic converter enough to to have a leak see how it runs if it better have exhaust systm fixed if u cant do it go to mufflr shop see if they can loosen exhaust before CATALYST NOT AFTER CATALYST
Could be your turbo intercooler hose. You can hear it and your power will be way down. (If it's a turbo)
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