its still not fixed.....

Final question - if my car is hesitating under load at 50 ish with the new MAF is it cos the units knackd cos the old one works fine, as I'm not sure whether to send it back as faulty (and have the guy test it and say its fine - no refund) or simply return it "as my mechanic has found the fault and I only ordered it just in case sir...."

?????????????