td5 defender 99 lurches at low revs

hi just bought my defender noticed at slow speed 1st gear tickover when I press accelerator it lurches almost uncontrollably like its missing. when its driving at normal speeds its fine but in dead slow traffic its terrible changed injector loom today no difference unplugged air flow meter no difference its been de egrd no cat silicon intercooler hoses at a bit of a loss plugged it into snap solus scanner today cleared old fault codes comes up with egr, wastegate open circuit, air temp open circuit and usual abs stuff haven't got egr or waste gate actuator not sure about air temp one but while running air flow was40-45 on tickover and over 300 doing 70 in fifth is this a normal reading as I said tried unplugging didn't change symptom air temp was reading in scan mode help

mines a 1999td5 air temp is taken from the map sensor on the inlet manifold you could try unplugging this and see if that makes any difference,on the later td5 it has a temp reading on the aap sensor (air filter box) but the older ones don't.i had a problem with the map sensor were it would jump from 28 degrees to 130 go to limp then back to normal ended up buying hawkeye takes a lot of guessing out good luck

Air flow readings are on the low side, at tick oved should be 50-60 and at full belt around 600, Id say get a genuine or at least OEM air flow meter

thanks guys fitted air flow meter, waste gate springy bit still no better then fit later ecu msb000080 no more lurching did have msb101170 early 1998 version renowned for lurching throttle thanks to alive tunings expertise!!!