VW GOLF IV 1.6 Running rich and no power ? MYSTERIOUS FAULT !

Hi all.
I'm really out of ideas with this. VW golf 1.6 16v AZD engine. Year 2001.

Car suddenly suffered power loss, and started to run really rough. Moaning and tapping from engine when full throttle. Blue smoke from exhaust.
With partial throttle, managed to drive home.

Car starts fine and idles ok. And when you slowly press accelerator it revs up to 3500rpm, but then it starts to loose power and starts to run rough and revs drop. Then with accelerator pressed approx 1/3 and keeping it there for a while it starts to sort of cutting out/ revs go back and forth.
There was a fault code from egr valve, and fuel trim running rich.
With emissions tester it was confirmed, that it is running really rich.

Egr valve was faulty, and it's now new, but no affect to main problem.
Have done cylinder compression test and leakage test, those were ok.
In livedata engine temperature sensor showing same as the temp gauge, and seems reasonable.
There is no intake air leaks (tested this with pressurized smoke machine)

Have already tried these:

- New egr valve
- New spark plugs
- New cam sensor
- New crank sensor
- New map sensor
- Two new coils (had them already, so tried with these)

Also have checked fuel pressure. Readings 2.5bar at idle and about 3bar at 2500rpm. Seems ok ?
Checked ecu connectors, there was no oxidation. Tried to wiggle wiring harnesses, with no affect.
Have tried to disconnect lambda sensors one at the time, but symptoms remains.
Have tried to disconnect injectors one at the time, but there was no affect to the moaning and tapping with full throttle and with partial throttle it still went back and forth and was cutting out.

ANY IDEAS ???
Please ! I'm losing my mind with this...

The car running rich and blue smoke is burning oil I had aa car that burned oil but it never affected the fuel trims. I should test the 02 sensor had an older car with shorted wire to the 02 sensor the car was running really rich does the oil on dipstick smell fuel. I don't think it is a problem with the fuel pump I guess you should have higher pressure then but I don't know the spec. If the car is running extremely rich I think the smoke from tail-pipe should be white not blue. You should also check for faulty fuel injector. Try a cylinder drop down test if it possible unplug a fuel injector and listen for rpm change.

Blue smoke is from burning oil, white smoke is indicative of a blown head gasket or cracked head or block where you have water or coolant intrusion into the combustion chamber and lastly, black smoke is related to a very rich condition. IIRC.

Is it possible that your car is in some kind of "limp" mode similar to the Audi that SD had with the bad engine mount? The mount did more than secure the engine, it went bad (as motor mounts do) but it had a sensor that informed the PCU of the defect and limited the output of the engine for safety reasons. The engineers thought it might be dangerous driving around with a bad MM. Years ago, I had a Fairlane GT 390 with a bad MM and the darn engine would flip over a bit which caused the throttle linkage to bind causing a full throttle issue making for an interesting drive. The motor would eventually (fairly quickly) drop back down and the idle would return to normal until it happened again.

I am not saying you have a MM issue, just that you may have something causing the symptoms you are describing which may be causing a limp mode.

Hello everyone,

What are telling O2 sensors to pcm?

When you unpluged O2 sensors, what voltage pcm/scanner show you?

What numbers do you have at trims and MAP?

I dont think, that it is going into limp mode. Even in limp mode I dont think it should be moaning and tapping. Nor running so rich. I will post trim and map readings tomorrow, when back at the car.
If it is burning oil, what could be the reason and would that cause these symptoms?
Thank you all for your replies!

And I did disconnect injectors one by one, with no effect to symptoms. Beside that it of course ran with three cylinders and therefore it was running even worse. But could it still be a leaking injectors that could cause these symptoms?

SOLVED !

Catalysator was clogged.
Possibly because of the faulty egr, witch has been stuck open for a longer time.

Good news!!!

Nice to know. Thanks.