HELP VR6 problem Again

[Hakan]

Was driving the other day when it was 36 degrees to work and my car wasnt making power after 3000rpm . The revs would just drop down on full throttle but all fine below 3000rpm and light throttle . Then when i got home i found that my AFM wiring was melted to the main engine loom so i opened up the loom and replace every single wire 1 by 1 . I went for a test and it was all fine for a bit then started not making power on certain rev ranges it just feels dead no torque.
its feels strong from idle to 2000 then its dead until 3.5 , then abit more grunt till 4.5 then nothing till limiter. I want to get the codes read but i have no time during the day

ive had this problem before but only happened twice then went away for ages till now. Im starting to think that it could be a blocked catalytic converter since ive got a straight pipe after it.
2nd is my air flow meter could be fauly. I have tested it and it dies when i take the plug off.
3rd oxygen sensor
if i cant fix ill dump the shell , buy a 2 door , rebuild my other engine and turbo with a standalone no more problems other then changing tyres.

Im just lost guys Im out of ideas
also I always use Shell 98 premium

Thanks for reading this Headache

[SpeciP3]

Does sound like a sensor problem, but it's a bit odd if it keeps coming on and off, so perhaps is related to your wiring issues? Would say AFM would be the most likely culprit
Also is there enough fuel? Does your pump whine or make any noises? This is less likely if the problem resolves at higher revs, though there is the possibility of fuel restriction which again may relate back to a sensor.
Have had a similar problem, but only if I try to give it the beans too quickly, feels like you've taken your foot off the pedal.

When you tested the AFM did you drive the car with it disconnected or just let it idle?

[Hakan]

I tested it with fresh 98 octane . but ive have never changed the fuel filter since ive bought it maybe its blocked ?
yes it feels like youve taken your foot off the pedal when your full throttle its very weird . i have disconnected the plug and then tried starting it but wont start without accelerating and wont idle when it starts so it should be okay . i might try making a test pipe to see if its the cat thats blocked . This just happened out of nowhere car was running so good where ive dyno'd it only a couple of months ago and made 107 kwatw .

[Hakan]

I cleaned the MAF sensor with maf cleaner also did a global download for 10 minutes . and then left the ignition on for 5 minutes without starting . Then restarted engine let it idle for another 5 minutes . then went on a slow drive and putting more Load and revs as it warmed up. now its fixed and feels a bit more torquey through the rev range .

[Water Boy]

Good new news. Looks after it. Need all the Mk3's at ILV.