During the time I had a vacuum hose going to the tranny bad, the engine had lots of power. A standing start leave black marks on the street.

Now, after the tranny / vacuum fix, the idle is rough, also little too low at 500, and when accelerating, there's not enough power. Releasing a little the accelerator, and the car gain power.

Any idea what this might be? MAF / EGR / TPS?

Anybody has any clue? The show could not solve this mystery until now...

Help, anybody? I am lost with that...

check,the eha,the ovp and the fuel /air ratio.a bad eha causes hard cold starts very ruff idle,ovp controls voltage to all the engne control sensors,also you may want to chech the engine idle control valve,it fills with carbon,and may b sticking,remove clean it,test drive.gtood luck.

This chap has the later electronic (or HFM) system - it doesn't have EHA, ICV etc. You're thinking of the earlier CIS (or KE) system.

I am a KE person but from the experience I had with my son's Golf Gti, I'd start with the MAF - try cleaning it with contact cleaner and one of those things one uses to clean out a baby's ears. The Gti is running fine 18 months after the MAF clean but the baby's got filthy ears.

Good luck to you.

RayH

oh,maf i love tem things,i just replace 4 of tbhemin my sis buick,the ecm was blwin them,they really mess up the proper running of the engne,but be very very carefull sticking things in there,that element s very delicate,use that maf cleaner.the spray one .its not a cheap part

I cleaned the MAF already, using contact cleaner. MAF cleaner is unfortunately not available here. I also cleaned the throttle body with carb cleaner, and changed the spark plugs. It helped a little, at least related to the bad idle, but not regarding power loss.

The whole story is very strange.
I got the car, all was perfect, lots of power, transmission shift smooth.
The only issue I had was the hard starting when the engine is hot.
I got a new CPS, and a mechanics installed it. At that same moment, the transmission shifted very hard.
What happened was that the mechanics has the vacuum line going to the transmission between the housing and the CPS and squeezed the line.
It took me a week to figure that out (he wanted to rebuild the transmission!).
So I told him to remove the CPS, plug a new line, and screw it all together.
He did, then adjusted here and there a little, and the result is, no power, rough idle, strange shifting behavior etc.
Now, weeks later, I still could not solve the issues. I have no idea what he could have done to cause such symptoms.
Of course, he want money, now he told me to "reset" the car to default via his Star Diagnosis, and want another $80 for that.