
Long story so sorry in advance.
Started when I was testing my 99 tezz, I had to change my straight through to put a cat in for test. The car started limiting out around 6/6.5 rpm but just assumed it was as a result of the cat, she was still hitting vvti though. She passed test and changed back to the straight through exhaust but was still limiting out early and started to get worse. She started to limit at 5.5rpm then dropped to 4.5rpm. At this stage she was down on power, not hitting vvti and limiting at different stages. I changed the crank shaft sensor (advised to do this) no difference. I then changed bank 1 vvti soliniod and she was going up in the revs but still not hitting vvti. Changed bank 2, no difference and now is limiting at 3rpm and popping like mad when hitting near there.
To date I have:
Cleaned out the MAF sensor and throttle body (as she was ideling funny)
Changed the crank shaft sensor (no difference)
Changed bank 1 and 2 vvti sensor (slight improvement but still not right and has since started to deteriorate)
No engine management light up (light comes on so it's working)
Ran a diagnostic and no related faults reading
Any idea what it could be?
I may have forgotten things so will update if anything comes to mind.