I posted before about this but no one seemed to know what I was talking about.
When I intalled my (Star) turbo kit a while back, on occation my engine would stop at 4000 rpms.
It felt exactly like my engine was being governed and no matter what gear I was in or how slow I tried to surpass the marker it ceased the engine from continuing.
I recently have taken my turbo kit off:-/, and now I can't reset it(turning the key all the way past ign closest to me and then restarting) to alleviate the problem.
I could take it to a shop to run diagnostics but that could get pricey.
I might have to take it there anyways but if anyone has had any experience or just wants to take a stab at it that would be cool.

im no genious, but maybe the map sensor isnt seein the correct voltage, like too much or too little and cutting fuel at 4k rpms

does the car blow smoke out the exhaust

do u just stay at 4000rpms like a rev limiter or do u get the fuel cut and have the engine shit on u?

i dont have a turbo, i have just been readin sum posts, so maybe that will help.

I have heard people talking about the engine going in to a "limp mode" and having a 4,000rpm rev limit, this could have been caused by the map sensor freaking out if you didn't have the VC1 hooked up right. Have you disconnected the computer for 15 minutes to reset it and clear the engine codes? Does it have any codes or is the CEL on?

Missing Car. . .
Contemplating Turbo. . . . .

http://hometown.aol.com/ohshootuhh/

Perf:
KYB AGX Struts
Neuspeed Sport Springs
5 Strut Bars (2 F/U, F/L, R/U, R/L)
Sprint Front Camber Kit
$15 Rear Camber Kit
Corbin's A/F Gauge
MSD DIS-2 Ignition System
Some Regrind Cams that need High Compression (which I don't have)
Ported Intake Manifold
Ported Throttle Body
Nameless Cold Air Intake with a K&N Filter
Custom 2 1/2 inch exhaust with Dual DTM Muffler
Empty Catalytic Convertor
Energy Suspension Motor Mount inserts
Hurricane_GS Short Shifter
Symborsky Shift Kit
Clutchmasters Stage 3 Modular
225/50/16inch Wheels and Tires


Audio:
Alpine CD Head Unit
Alpine Flex4 25W X 4 for Fronts and Rears
Alpine V-12 450W X 1 for Subs
Infinity Reference Series 5 1/4 and 1 inch tweeter component systems for fronts and rears
Blaupunkt 3 way 6x9's in the rears
3 MTX 5000 10" 12 ohm subs running 4 ohms mono

my car used to do that.. and then I'd let it idle and it would die. for some reason.. it just stopped doing it. probably cuz I kicked it enough times.. it decided to quit pissing me off. FUCKIN MITSUBISHI!!!