Further to this issue I have a very similar issue
Can anybody help. I have had a similar issues with P0299 and P1103 errors. They clear every time I reset I erase with my tester . I tend to get the limp function kick in at around 2000-2500 revs in 4th gear.
I have put a new vacuum solenoid valve on, check the vacuum pipes and the vacuum valve holds in position on the turbo at idle.
I checked the voltages on the MAF sensor. So I checked the main 12v (14.2 v running) positive and negative and then checked across the sensor wires where I'm getting 7.12 volts at idle and 7.6 volts at 3000 revs.
Are these values correct or is there an issue here.
What others things can I check.

Regards doyugsolv