Please Help Diagnose

[Smoke777x]

Well i have bought a 95 gst with an evo 3 motor in it about 4 weeks ago for 900$. The guy i bought it from didnt seem to know what exactly was wrong with it but the car would idle for about ten minuts fine, then the idle would start to drop until the car would shut down. My fried who is a mechaninc told me its probbably the MAF sesnsor so i changed it yesterday and now it idles fine. I have drove it around the block a couple of times and its the best feeling in the world since i just stepped up from a 97 gs, well the probelem is when i was driving the clutch paddle would sometimes just floor its self all the way like it just lost pressure then when i slow down and pull it back i would regain clutch pressure for a littel my friend told me that its probably the throw out bearing. Also the car smoked more than normal and it smelled like oil but i could tell what color smoke it was because i didt register the car yet so i had to drive in the night time but the smoke was either white or blue but deffinatly not black. The car does not smoke when its idling.

 

[1g_tsi_awd]

So if you push the clutch lightly it sinks to the floor? You might have what RRE calls "ghost pedal" I believe which entails a new master cylinder.

If it is white smoke, that would probably mean headgasket I believe. And if it is blue that could be blowby or something.

 

[Smoke777x]

Is there anyway i can check my self if its the master cylynder, also can i check the crankshaft play? The car also has the oil light on which dimms when the idle is at about 800-900 rpm

 

[spoonman]

The blue smoke coming out of the tail pipe sounds like bad rings that are letting oil in the cylinders. The oil light could be dimming because, at idle your oil pressure is lower, my 1g does it also. For the clutch check the fluid and inspect the hydraulic lines going to it from the transmisson.

 

[1g_tsi_awd]

Well, what are the symptoms? If you push lightly does the clutch stick to the floor?

 

[1g_tsi_awd]

2G "Ghost Pedal"

On very light foot pressure on a 2Gthe pedal drops to the floor all by it's self. ?? Yes. The little rubber seal in the pic above gets a little nick in it or a piece of dirt under it. On a regular pedal push, the seal seals fine and the clutch works normally. On a very light push, the seal does not seal well and fluid will bypass it. Since the 2Gs have a heavy assist spring, the additional assist is enough pressure to keep the pedal going towards the floor all alone. Quite disturbing to watch. Replacing or rebuilding the master cylinder will fix this.

(Courtesy of RRE)