Rough Idle. Immediately Stalls. Help!

[NavajoDave]

Last night was taking my buddy home and I decide to let him drive it (big mistake) because he has had a manual car for like 5 years. Mind you my car is not tuned yet for stage 3, doesn't have proper fueling, and just did a tip to 6mt swap so basically every light is on already. Next thing I know the car is reved to about 5K and then immediately stalls. He try's to restart the car and the idle is very harsh and immediately stalls. Hope the engine is not blown up, but haven't had a chance to make it my mechanic to throw the vag com on it. Haven't gotten any major messages on the screen besides wind sheld wiper fluid, but then again my middle screen above the miles till empty is pixelated so I'm not sure. No oil on the ground and nothing looks weird under the hood.

Another note is that my mechanic had been messjng with the electronics to install my 02 sensor and also my speed sensor earlier yesterday, so might be electronic related.

Let me know what you guys think.

[Factis]

I think your car is 15 years old, probably has a ton of miles and why would you do this? Just to start.

Alternator. Throttle body / intake valves. Injectors even. A/F Ratio. Ignition timing.

Good luck :\

[Mr.Z]

big boost/vacuum leak.

[zillarob]

Unplug the maf. If it gets better, boost leak.
If the vss is jacked, will have a 5k rev limit.

[NavajoDave]

Turned out to be a boost leak at the TBB.